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June 24, 2020

Ekans Ransomware: Insights on OT Cyber Attacks

Uncover the impacts of the Ekans ransomware attack on operational technology and what organizations can do to enhance their cybersecurity posture.
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.
Written by
David Masson
VP, Field CISO
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24
Jun 2020

In recent weeks, the security industry has become acutely aware of the challenges surrounding OT protection, with the EKANS ransomware attacks on Honda and the Enel Group demonstrating how novel threats continue to slip through the cracks of security systems in ICS environments. What’s more, with such attacks resulting in loss of productivity and damage to critical infrastructure, the need for a cyber security strategy that bridges both OT and IT technology is increasingly urgent.

The recent EKANS ransomware has been making waves in security circles because of its ability to target 64 specific ICS mechanisms in its ‘kill chain’. Standard attacks target ICS environments through vulnerabilities in IT infrastructure, pivoting through unpatched software to reach OT machinery, rather than heading straight for the jugular. The EKANS ransomware targeted ICS vulnerabilities directly and can be considered the first of its kind – marking a significant evolution in attacker techniques. Before now, ICS machinery-specific ransomware had either been an academic theory or a marketing tool.

Technical analysis

Written in the Go programming language, EKANS has additional obfuscation abilities compared to other ransomware strains, which enable it to better evade detection. As will be seen in this analysis, the power of EKANS ransomware is two-fold – it is able to disguise its attack in the beginning stages, and when it does strike, it is targeted at industrial pain points.

The ransomware’s first port of call is to check if the victim has already been encrypted. If not, standard encryption library functions ensue. These involve both the execution of encryption operations and the deletion of Volume Shadow Copy back-ups – meaning the victim cannot simply retrieve duplicated data copies and circumvent the ransom.

Before the relevant files are encrypted, EKANS ransomware kills various ICS processes listed in a pre-programmed, hard-coded list. The affected applications include GE’s Proficy data historian, GE Fanuc automation software, FLEXNet licensing server instance, Thingworx monitoring and management software, and Honeywell’s HMIWeb application – all specific to ICS environments.

proficyclient.exe
vmacthlp.exe
msdtssrvr.exe
sqlservr.exe
msmdsrv.exe
reportingservicesservice.exe
dsmcsvc.exe
winvnc4.exe
client.exe
collwrap.exe
bluestripecollector.exe

Figure 1: A small excerpt of the ICS-related processes targeted in the EKANS ‘kill list’

While stalling these processes doesn’t necessarily bring industrial plants crashing to a halt, it does reduce visibility and potentially make machine operations unpredictable. In the case of Honda’s attack, manufacturing operations across the US, the UK, and Turkey were suspended. With a workforce of 220,000 people worldwide, shutting down several factories and sending employees home results in a dramatic loss of production hours and employee salaries – not to mention the costs of getting systems up and running without giving in to ransom demands.

EKANS then goes one stage further. Once this initial kill chain has been executed, the ransomware starts encrypting data. Five randomly generated letters are added at the end of each original file extension. This in itself is unusual, as most ransomware encrypts data with a specific key.

Figure 2: Encryption results of EKANS ransomware

Rather than targeting specific devices or systems, EKANS ransomware looks to take down the entire network, which is part of what makes it such an aggressive style of ransomware. However, it lacks a self-propagating mechanism, so it has to be manually introduced to ICS environments. Malicious payloads hidden in links and attachments within emails are the primary mechanism used to introduce the ransomware. From there, EKANS exploits vulnerable and unpatched services, seeding itself across the entire business via script.

When the encryption process has been completed, a ransom note is displayed, requesting a covert financial exchange for a decryption key over the encrypted email platform CTemplar. In the case of both Honda and the Enel Group, they were told to contact CarrolBidell@tutanota[.]com for further information. The attackers also offered to send several decrypted files to prove the legitimacy of the encryption key.

| What happened to your files?
--------------------------------------------
We breached your corporate network and encrypted the data on your computers. The encrypted data includes documents, databases, photos and more –
all were encrypted using a military grade encryption algorithms (AES-256 and RSA-2048). You cannot access those files right now. But dont worry!
You can still get those files back and be up and running again in no time.
--------------------------------------------
| How to contact us to get your files back?
--------------------------------------------
The only way to restore your files is by purchasing a decryption tool loaded with a private key we created specifically for your network.
Once run on an effected computer, the tool will decrypt all encrypted files – and you resume day-to-day operations, preferably with
better cyber security in mind. If you are interested in purchasing the decryption tool contact us at %s
--------------------------------------------
| How can you be certain we have the decryption tool?
--------------------------------------------
In your mail to us attach up to 3 files (up to 3MB, no databases or spreadsheets).

Figure 3: Partial view of EKANS ransomware note

Honda has refrained from stating what specific plant capabilities were affected by the EKANS attack, however it has publicly affirmed that production operations have been affected in multiple factories across the world. Their visibility and control systems were disrupted significantly enough to suspend manufacturing.

Becoming immune to ransomware

While the EKANS ransomware leverages fairly crude techniques and is only able to halt processes rather than control ICS mechanisms, it represents a new frontier in OT cyber-attacks. ICS offensives will continue to evolve – with greater control over machinery a likely avenue of exploration for cyber-criminals.

What is clear from the Honda attack is that even some of the world’s largest global conglomerates are susceptible to these kind of ransomware attacks. What is needed to protect factory floors from such attacks is a cyber security solution that can detect the most subtle signals of threat, learning on the job to understand what is ‘normal’ for each unique ICS environment.

Darktrace’s AI learns the normal ‘patterns of life’ for every user, device, and controller across both OT and IT. By continuously analyzing data across organizations’ systems, the AI’s unique understanding of how each facet of a business and a dynamic workforce interacts ensures that any malicious activity is detected seconds after it emerges. In the case of EKANS, this self-learning approach would have identified a number of anomalous behaviors pertaining to the originally infected device, including beaconing to a rare destination and the unusual connections to encryption software.

Complementing Darktrace’s threat detection is the AI’s Autonomous Response abilities, which neutralize threats with surgical precision – allowing business activity to continue as normal. Autonomous Response has already proven itself successful in stopping ransomware attacks, preventing damaging operational outages at manufacturing facilities, hospitals, and municipalities around the world.

Conclusion

EKANS revealed that attackers are beginning to successfully target both IT and OT systems with one attack, making the need for security programs that can bridge this gap more urgent than ever. The ability to defend both environments with a single security solution ensures holistic protection for the entire organization. By correlating disparate data points across SaaS, email, cloud, traditional network, and OT environments, Cyber AI can identify and stop even the most sophisticated attacks.

The reality is that threats in the OT sphere will continue to evolve, becoming faster and more furious than ever. Given the potential damage ransomware can cause, security that can defend industrial systems along with dynamic workforces – detecting and stopping fast-acting threats across a complex business – has become more important than ever. The functionality of industrial systems depends on it.

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.
Written by
David Masson
VP, Field CISO

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October 30, 2025

WSUS Exploited: Darktrace’s Analysis of Post-Exploitation Activities Related to CVE-2025-59287

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Introduction

On October 14, 2025, Microsoft disclosed a new critical vulnerability affecting the Windows Server Update Service (WSUS), CVE-2025-59287.  Exploitation of the vulnerability could allow an unauthenticated attacker to remotely execute code [1][6].

WSUS allows for centralized distribution of Microsoft product updates [3]; a server running WSUS is likely to have significant privileges within a network making it a valuable target for threat actors. While WSUS servers are not necessarily expected to be open to the internet, open-source intelligence (OSINT) has reported  thousands of publicly exposed instances that may be vulnerable to exploitation [2].

Microsoft’s initial ‘Patch Tuesday’ update for this vulnerability did not fully mitigate the risk, and so an out-of-band update followed on October 23 [4][5] . Widespread exploitation of this vulnerability started to be observed shortly after the security update [6], prompting CISA to add CVE-2025-59287 to its Known Exploited Vulnerability Catalog (KEV) on October 24 [7].

Attack Overview

The Darktrace Threat Research team have recently identified multiple potential cases of CVE-2025-59287 exploitation, with two detailed here. While the likely initial access method is consistent across the cases, the follow-up activities differed, demonstrating the variety in which such a CVE can be exploited to fulfil each attacker’s specific goals.

The first signs of suspicious activity across both customers were detected by Darktrace on October 24, the same day this vulnerability was added to CISA’s KEV. Both cases discussed here involve customers based in the United States.

Case Study 1

The first case, involving a customer in the Information and Communication sector, began with an internet-facing device making an outbound connection to the hostname webhook[.]site. Observed network traffic indicates the device was a WSUS server.

OSINT has reported abuse of the workers[.]dev service in exploitation of CVE-2025-59287, where enumerated network information gathered through running a script on the compromised device was exfiltrated using this service [8].

In this case, the majority of connectivity seen to webhook[.]site involved a PowerShell user agent; however, cURL user agents were also seen with some connections taking the form of HTTP POSTs. This connectivity appears to align closely with OSINT reports of CVE-2025-59287 post-exploitation behaviour [8][9].

Connections to webhook[.]site continued until October 26. A single URI was seen consistently until October 25, after which the connections used a second URI with a similar format.

Later on October 26, an escalation in command-and-control (C2) communication appears to have occurred, with the device starting to make repeated connections to two rare workers[.]dev subdomains (royal-boat-bf05.qgtxtebl.workers[.]dev & chat.hcqhajfv.workers[.]dev), consistent with C2 beaconing. While workers[.]dev is associated with the legitimate Cloudflare Workers service, the service is commonly abused by malicious actors for C2 infrastructure. The anomalous nature of the connections to both webhook[.]site and workers[.]dev led to Darktrace generating multiple alerts including high-fidelity Enhanced Monitoring alerts and alerts for Darktrace’s Autonomous Response.

Infrastructure insight

Hosted on royal-boat-bf05.qgtxtebl.workers[.]dev is a Microsoft Installer file (MSI) named v3.msi.

Screenshot of v3.msi content.
Figure 1: Screenshot of v3.msi content.

Contained in the MSI file is two Cabinet files named “Sample.cab” and “part2.cab”. After extracting the contents of the cab files, a file named “Config” and a binary named “ServiceEXE”. ServiceEXE is the legitimate DFIR tool Velociraptor, and “Config” contains the configuration details, which include chat.hcqhajfv.workers[.]dev as the server_url, suggesting that Velociraptor is being used as a tunnel to the C2. Additionally, the configuration points to version 0.73.4, a version of Velociraptor that is vulnerable to CVE-2025-6264, a privilege escalation vulnerability.

 Screenshot of Config file.
Figure 2: Screenshot of Config file.

Velociraptor, a legitimate security tool maintained by Rapid7, has been used recently in malicious campaigns. A vulnerable version of tool has been used by threat actors for command execution and endpoint takeover, while other campaigns have used Velociraptor to create a tunnel to the C2, similar to what was observed in this case [10] .

The workers[.]dev communication continued into the early hours of October 27. The most recent suspicious behavior observed on the device involved an outbound connection to a new IP for the network - 185.69.24[.]18/singapure - potentially indicating payload retrieval.

The payload retrieved from “/singapure” is a UPX packed Windows binary. After unpacking the binary, it is an open-source Golang stealer named “Skuld Stealer”. Skuld Stealer has the capabilities to steal crypto wallets, files, system information, browser data and tokens. Additionally, it contains anti-debugging and anti-VM logic, along with a UAC bypass [11].

A timeline outlining suspicious activity on the device alerted by Darktrace.
Figure 3: A timeline outlining suspicious activity on the device alerted by Darktrace.

Case Study 2

The second case involved a customer within the Education sector. The affected device was also internet-facing, with network traffic indicating it was a WSUS server

Suspicious activity in this case once again began on October 24, notably only a few seconds after initial signs of compromise were observed in the first case. Initial anomalous behaviour also closely aligned, with outbound PowerShell connections to webhook[.]site, and then later connections, including HTTP POSTs, to the same endpoint with a cURL user agent.

While Darktrace did not observe any anomalous network activity on the device after October 24, the customer’s security integration resulted in an additional alert on October 27 for malicious activity, suggesting that the compromise may have continued locally.

By leveraging Darktrace’s security integrations, customers can investigate activity across different sources in a seamless manner, gaining additional insight and context to an attack.

A timeline outlining suspicious activity on the device alerted by Darktrace.
Figure 4: A timeline outlining suspicious activity on the device alerted by Darktrace.

Conclusion

Exploitation of a CVE can lead to a wide range of outcomes. In some cases, it may be limited to just a single device with a focused objective, such as exfiltration of sensitive data. In others, it could lead to lateral movement and a full network compromise, including ransomware deployment. As the threat of internet-facing exploitation continues to grow, security teams must be prepared to defend against such a possibility, regardless of the attack type or scale.

By focussing on detection of anomalous behaviour rather than relying on signatures associated with a specific CVE exploit, Darktrace is able to alert on post-exploitation activity regardless of the kind of behaviour seen. In addition, leveraging security integrations provides further context on activities beyond the visibility of Darktrace / NETWORKTM, enabling defenders to investigate and respond to attacks more effectively.

With adversaries weaponizing even trusted incident response tools, maintaining broad visibility and rapid response capabilities becomes critical to mitigating post-exploitation risk.

Credit to Emma Foulger (Global Threat Research Operations Lead), Tara Gould (Threat Research Lead), Eugene Chua (Principal Cyber Analyst & Analyst Team Lead), Nathaniel Jones (VP, Security & AI Strategy, Field CISO),

Edited by Ryan Traill (Analyst Content Lead)

Appendices

References

1.        https://nvd.nist.gov/vuln/detail/CVE-2025-59287

2.    https://www.bleepingcomputer.com/news/security/hackers-now-exploiting-critical-windows-server-wsus-flaw-in-attacks/

3.    https://learn.microsoft.com/en-us/windows-server/administration/windows-server-update-services/get-started/windows-server-update-services-wsus

4.    https://www.cisa.gov/news-events/alerts/2025/10/24/microsoft-releases-out-band-security-update-mitigate-windows-server-update-service-vulnerability-cve

5.    https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59287

6.    https://thehackernews.com/2025/10/microsoft-issues-emergency-patch-for.html

7.    https://www.cisa.gov/known-exploited-vulnerabilities-catalog

8.    https://www.huntress.com/blog/exploitation-of-windows-server-update-services-remote-code-execution-vulnerability

9.    https://unit42.paloaltonetworks.com/microsoft-cve-2025-59287/

10. https://blog.talosintelligence.com/velociraptor-leveraged-in-ransomware-attacks/

11. https://github.com/hackirby/skuld

Darktrace Model Detections

·       Device / New PowerShell User Agent

·       Anomalous Connection / Powershell to Rare External

·       Compromise / Possible Tunnelling to Bin Services

·       Compromise / High Priority Tunnelling to Bin Services

·       Anomalous Server Activity / New User Agent from Internet Facing System

·       Device / New User Agent

·       Device / Internet Facing Device with High Priority Alert

·       Anomalous Connection / Multiple HTTP POSTs to Rare Hostname

·       Anomalous Server Activity / Rare External from Server

·       Compromise / Agent Beacon (Long Period)

·       Device / Large Number of Model Alerts

·       Compromise / Agent Beacon (Medium Period)

·       Device / Long Agent Connection to New Endpoint

·       Compromise / Slow Beaconing Activity To External Rare

·       Security Integration / Low Severity Integration Detection

·       Antigena / Network / Significant Anomaly / Antigena Alerts Over Time Block

·       Antigena / Network / Significant Anomaly / Antigena Enhanced Monitoring from Server Block

·       Antigena / Network / External Threat / Antigena Suspicious Activity Block

·       Antigena / Network / Significant Anomaly / Antigena Significant Server Anomaly Block

List of Indicators of Compromise (IoCs)

IoC - Type - Description + Confidence

o   royal-boat-bf05.qgtxtebl.workers[.]dev – Hostname – Likely C2 Infrastructure

o   royal-boat-bf05.qgtxtebl.workers[.]dev/v3.msi - URI – Likely payload

o   chat.hcqhajfv.workers[.]dev – Hostname – Possible C2 Infrastructure

o   185.69.24[.]18 – IP address – Possible C2 Infrastructure

o   185.69.24[.]18/bin.msi - URI – Likely payload

o   185.69.24[.]18/singapure - URI – Likely payload

The content provided in this blog is published by Darktrace for general informational purposes only and reflects our understanding of cybersecurity topics, trends, incidents, and developments at the time of publication. While we strive to ensure accuracy and relevance, the information is provided “as is” without any representations or warranties, express or implied. Darktrace makes no guarantees regarding the completeness, accuracy, reliability, or timeliness of any information presented and expressly disclaims all warranties.

Nothing in this blog constitutes legal, technical, or professional advice, and readers should consult qualified professionals before acting on any information contained herein. Any references to third-party organizations, technologies, threat actors, or incidents are for informational purposes only and do not imply affiliation, endorsement, or recommendation.

Darktrace, its affiliates, employees, or agents shall not be held liable for any loss, damage, or harm arising from the use of or reliance on the information in this blog.

The cybersecurity landscape evolves rapidly, and blog content may become outdated or superseded. We reserve the right to update, modify, or remove any content

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Emma Foulger
Global Threat Research Operations Lead

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October 24, 2025

Patch Smarter, Not Harder: Now Empowering Security Teams with Business-Aligned Threat Context Agents

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Most risk management programs remain anchored in enumeration: scanning every asset, cataloging every CVE, and drowning in lists that rarely translate into action. Despite expensive scanners, annual pen tests, and countless spreadsheets, prioritization still falters at two critical points.

Context gaps at the device level: It’s hard to know which vulnerabilities actually matter to your business given existing privileges, what software it runs, and what controls already reduce risk.

Business translation: Even when the technical priority is clear, justifying effort and spend in financial terms—especially across many affected devices—can delay action. Especially if it means halting other areas of the business that directly generate revenue.

The result is familiar: alert fatigue, “too many highs,” and remediation that trails behind the threat landscape. Darktrace / Proactive Exposure Management addresses this by pairing precise, endpoint‑level context with clear, financial insight so teams can prioritize confidently and mobilize faster.

A powerful combination: No-Telemetry Endpoint Agent + Cost-Benefit Analysis

Darktrace / Proactive Exposure Management now uniquely combines technical precision with business clarity in a single workflow.  With this release, Darktrace / Proactive Exposure Management delivers a more holistic approach, uniting technical context and financial insight to drive proactive risk reduction. The result is a single solution that helps security teams stay ahead of threats while reducing noise, delays, and complexity.

  • No-Telemetry Endpoint: Collects installed software data and maps it to known CVEs—without network traffic—providing device-level vulnerability context and operational relevance.
  • Cost-Benefit Analysis for Patching: Calculates ROI by comparing patching effort with potential exploit impact, factoring in headcount time, device count, patch difficulty, and automation availability.

Introducing the No-Telemetry Endpoint Agent

Darktrace’s new endpoint agent inventories installed software on devices and maps it to known CVEs without collecting network data so you can prioritize using real device context and available security controls.

By grounding vulnerability findings in the reality of each endpoint, including its software footprint and existing controls, teams can cut through generic severity scores and focus on what matters most. The agent is ideal for remote devices, BYOD-adjacent fleets, or environments standardizing on Darktrace, and is available without additional licensing cost.

Darktrace / Proactive Exposure Management user interface
Figure 1: Darktrace / Proactive Exposure Management user interface

Built-In Cost-Benefit Analysis for Patching

Security teams often know what needs fixing but stakeholders need to understand why now. Darktrace’s new cost-benefit calculator compares the total cost to patch against the potential cost of exploit, producing an ROI for the patch action that expresses security action in clear financial terms.

Inputs like engineer time, number of affected devices, patch difficulty, and automation availability are factored in automatically. The result is a business-aligned justification for every patching decision—helping teams secure buy-in, accelerate approvals, and move work forward with one-click ticketing, CSV export, or risk acceptance.

Darktrace / Proactive Exposure Management Cost Benefit Analysis
Figure 2: Darktrace / Proactive Exposure Management Cost Benefit Analysis

A Smarter, Faster Approach to Exposure Management

Together, the no-telemetry endpoint and Cost–Benefit Analysis advance the CTEM motion from theory to practice. You gain higher‑fidelity discovery and validation signals at the device level, paired with business‑ready justification that accelerates mobilization. The result is fewer distractions, clearer priorities, and faster measurable risk reduction. This is not from chasing every alert, but by focusing on what moves the needle now.

  • Smarter Prioritization: Device‑level context trims noise and spotlights the exposures that matter for your business.
  • Faster Decisions: Built‑in ROI turns technical urgency into executive clarity—speeding approvals and action.
  • Practical Execution: Privacy‑conscious endpoint collection and ticketing/export options fit neatly into existing workflows.
  • Better Outcomes: Close the loop faster—discover, prioritize, validate, and mobilize—on the same operating surface.

Committed to innovation

These updates are part of the broader Darktrace release, which also included:

1. Major innovations in cloud security with the launch of the industry’s first fully automated cloud forensics solution, reinforcing Darktrace’s leadership in AI-native security.

2. Darktrace Network Endpoint eXtended Telemetry (NEXT) is revolutionizing NDR with the industry’s first mixed-telemetry agent using Self-Learning AI.

3. Improvements to our OT product, purpose built for industrial infrastructure, Darktrace / OT now brings dedicated OT dashboard, segmentation-aware risk modeling, and expanded visibility into edge assets and automation protocols.

Join our Live Launch Event

When? 

December 9, 2025

What will be covered?

Join our live broadcast to experience how Darktrace is eliminating blind spots for detection and response across your complete enterprise with new innovations in Agentic AI across our ActiveAI Security platform. Industry leaders from IDC will join Darktrace customers to discuss challenges in cross-domain security, with a live walkthrough reshaping the future of Network Detection & Response, Endpoint Detection & Response, Email Security, and SecOps in novel threat detection and autonomous investigations.

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Kelland Goodin
Product Marketing Specialist
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