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
Tony Jarvis
VP, Field CISO | Darktrace
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22
Mar 2022
In the lead-up to the 2020 US election, Microsoft and its partners attempted to bring down the pernicious Trickbot malware and reduce election tampering attempts. These efforts were successful, to an extent: the takedown effectively eliminated 94% of Trickbot’s infrastructure and massively reduced its influence in late 2020.
Malware rarely stays dead, however. We discussed previously how the arrests which followed REvil’s widespread attacks in 2021 have done little to disrupt that group’s Ransomware-as-a-Service operation, and how Ryuk ransomware fell into new hands after being abandoned by its creators.
Trickbot has seen a resurrection of even greater proportions. By June 2021, when Darktrace detected a Trickbot intrusion in one of its customer environments, the malware was far from a forgotten, ineffectual strain. It had instead become the most prevalent malware in the world.
It was only due to a last-minute activation of Darktrace’s Autonomous Response that this customer was able to avoid falling victim to a successful ransomware attack. Because it can take action at any stage of an attack, Autonomous Response could interrupt Trickbot even after it had taken root within the digital environment, and successfully prevent the execution of ransomware.
Trickbot takes root
The intrusion took place at a public administration organization in the EMEA region. Prior to Darktrace’s deployment, a single internal domain controller had been compromised by Trickbot, which then lay dormant for at least a month. By the time the malware began to take action, however, Darktrace’s AI had been deployed. Despite entering a compromised environment, the AI was able to differentiate between benign and malicious activity and immediately detect the threat, though at this point Autonomous Response was configured to not take any action without human confirmation.
Darktrace detected the compromised domain controller uploading a malicious DLL file – very likely Trickbot itself – to approximately 280 devices in the organization over SMB, and then using Windows Management Instrumentation (WMI) to configure and execute it. Despite Trickbot’s age and infamy, tools dependent on threat intelligence remained silent at this stage.
Figure 1: Timeline of the attack
How attackers resurrected Trickbot
Trickbot’s modular nature makes it a perfect gateway for a host of criminal activities, and keeps the malware itself adaptable and therefore hard to defend against. The action coordinated by Microsoft successfully took down the known IP addresses of multiple Trickbot command and control (C2) servers and temporarily prevented Trickbot operators from purchasing or leasing new ones. But it did not take long for the Trickbot infrastructure to be rebuilt, and in May and June of 2021 it was again deemed the most prevalent malware in a Global Threat Index.
Trickbot’s ability to evolve and circumvent existing OSINT was demonstrated in this attack, as Darktrace noticed 160 of the 280 compromised devices it had detected beginning to connect to a host of new C2 endpoints. None of these had OSINT associating them with malicious activity, but Darktrace considered the activity highly unusual in the context of previous behavior, and the security team were notified of this potential high-severity incident via a Proactive Threat Notification (PTN).
The attackers laid low for over a month, before the compromised devices were detected downloading masqueraded executable files and conducting anomalous scanning activity. These files were likely Ryuk ransomware payloads. By spacing out these stages of the attack, the threat actors made it harder for human teams to connect the dots and reveal the full scope of the threat.
Darktrace’s Cyber AI Analyst, which investigates and triages threats across entire digital environments, was able to piece these disparate events into a single attack narrative, however, and deliver a further PTN. Due to the severity of the situation, the customer submitted to Darktrace’s Ask the Expert (ATE) service to receive assistance with their threat response.
Figure 2: Cyber AI Analyst investigates suspicious executable files being spread to multiple internal devices
Autonomous Response shuts down a late-stage attack
Having understood the scale of the threat they now faced, the team activated Autonomous Response to take autonomous action to contain the threat. If Autonomous Response had been in place from the beginning, it would have stopped this attack in its earliest stages, while it was restricted to a single compromised domain controller. Crucially, however, Autonomous Response can take action at any stage of a ransomware attack.
Even at this late stage, it was able to halt the attackers and prevent Ryuk from being executed on the network. The AI blocked a chain of malicious activities including SMB enumeration, networking scanning, and suspicious outbound connections in seconds, disrupting the attack while enforcing normal business operations to ensure that the rest of the company’s work could continue uninterrupted.
With their C2 communications and lateral movement efforts disrupted, the attackers were unable to execute Ryuk, and the attack came to an end just in time. It is likely that this last-minute activation of Autonomous Response avoided widespread data encryption and possibly exfiltration, as well as the numerous costs which follow a successful ransomware attack even if a ransom is paid.
Deploying Autonomous Response before it’s too late
Despite only being activated once the attack had taken root, Darktrace was still able to distinguish malicious activity from normal business operations and stop the threat without causing disruption. Next time an attack strikes, this organization will be prepared with Autonomous Response in fully autonomous mode from the outset, ready to take action at the first sign of an emerging threat and minimize their remediation efforts.
The journey to fully autonomous security requires organizations to build trust in AI’s accuracy and decision-making. What this journey looks like for each individual organization will differ, but the need for technology that can autonomously respond to emerging threats is not a lesson any organization ought to learn the hard way.
Thanks to Darktrace analyst Sam Lister for his insights on the above threat find.
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.
Unpacking ClickFix: Darktrace’s detection of a prolific social engineering tactic
ClickFix is a social engineering technique that exploits human error through fake prompts, leading users to unknowingly run malicious commands. Learn how Darktrace detects and responds to such threats!
Darktrace investigated “PumaBot,” a Go-based Linux botnet targeting IoT devices. It avoids internet-wide scanning, instead using a C2 server to get targets and brute-force SSH credentials. Once inside, it executes remote commands and ensures persistence.
Modernising UK Cyber Regulation: Implications of the Cyber Security and Resilience Bill
The need for security and continued cyber resilience
The UK government has made national security a key priority, and the new Cyber Security and Resilience Bill (CSRB) is a direct reflection of that focus. In introducing the Bill, Secretary of State for Science, Innovation and Technology, Peter Kyle, recognised that the UK is “desperately exposed” to cyber threats—from criminal groups to hostile nation-states that are increasingly targeting the UK's digital systems and critical infrastructure[1].
Context and timeline for the new legislation
First announced during the King’s Speech of July 2024, and elaborated in a Department for Science, Innovation and Technology (DSIT) policy statement published in April 2025, the CSRB is expected to be introduced in Parliament during the 2025-26 legislative session.
For now, organisations in the UK remain subject to the 2018 Network and Information Systems (NIS) Regulations – an EU-derived law which was drafted before today’s increasing digitisation of critical services, rise in cloud adoption and emergence of AI-powered threats.
Why modernisation is critical
Without modernisation, the Government believes UK’s infrastructure and economy risks falling behind international peers. The EU, which revised its cybersecurity regulation under the NIS2 Directive, already imposes stricter requirements on a broader set of sectors.
The urgency of the Bill is also underscored by recent high-impact incidents, including the Synnovis attack which targeted the National Health Service (NHS) suppliers and disrupted thousands of patient appointments and procedures[2]. The Government has argued that such events highlight a systemic failure to keep pace with a rapidly evolving threat landscape[3].
What the Bill aims to achieve
This Bill represents a decisive shift. According to the Government, it will modernise and future‑proof the UK’s cyber laws, extending oversight to areas where risk has grown but regulation has not kept pace[4]. While the legislation builds on previous consultations and draws lessons from international frameworks like the EU’s NIS2 directive, it also aims to tailor solutions to the UK’s unique threat environment.
Importantly, the Government is framing cybersecurity not as a barrier to growth, but as a foundation for it. The policy statement emphasises that strong digital resilience will create the stability businesses need to thrive, innovate, and invest[5]. Therefore, the goals of the Bill will not only be to enhance security but also act as an enabler to innovation and economic growth.
Recognition that AI changes cyber threats
The CSRB policy statement recognises that AI is fundamentally reshaping the threat landscape, with adversaries now leveraging AI and commercial cyber tools to exploit vulnerabilities in critical infrastructure and supply chains. Indeed, the NCSC has recently assessed that AI will almost certainly lead to “an increase in the frequency and intensity of cyber threats”[6]. Accordingly, the policy statement insists that the UK’s regulatory framework “must keep pace and provide flexibility to respond to future threats as and when they emerge”[7].
To address the threat, the Bill signals new obligations for MSPs and data centres, timely incident reporting and dynamic guidance that can be refreshed without fresh primary legislation, making it essential for firms to follow best practices.
What might change in day-to-day practice?
New organisations in scope of regulation
Under the existing Network and Information Systems (NIS) Regulations[8], the UK already supervises operators in five critical sectors—energy, transport, drinking water, health (Operators of Essential Services, OES) and digital infrastructure (Relevant Digital Service Providers, RDSPs).
The Cyber Security and Resilience Bill retains this foundation and adds Managed Service Providers (MSPs) and data centres to the scope of regulation to “better recognise the increasing reliance on digital services and the vulnerabilities posed by supply chains”[9]. It also grants the Secretary of State for Science, Innovation and Technology the power to add new sectors or sub‑sectors via secondary legislation, following consultation with Parliament and industry.
Managed service providers (MSPs)
MSPs occupy a central position within the UK’s enterprise information‑technology infrastructure. Because they remotely run or monitor clients’ systems, networks and data, they hold privileged, often continuous access to multiple environments. This foothold makes them an attractive target for malicious actors.
The Bill aims to bring MSPs in scope of regulation by making them subject to the same duties as those placed on firms that provide digital services under the 2018 NIS Regulations. By doing so, the Bill seeks to raise baseline security across thousands of customer environments and to provide regulators with better visibility of supply‑chain risk.
The proposed definition for MSPs is a service which:
Is provided to another organisation
Relies on the use of network and information systems to deliver the service
Relates to ongoing management support, active administration and/or monitoring of AI systems, IT infrastructure, applications, and/or IT networks, including for the purpose of activities relating to cyber security.
Involves a network connection and/or access to the customer’s network and information systems.
Data centres
Building on the September 2024 designation of data centres as critical national infrastructure, the CSRB will fold data infrastructure into the NIS-style regime by naming it an “relevant sector" and data centres as “essential service”[10].
About 182 colocation facilities run by 64 operators will therefore come under statutory duties to notify the regulator, maintain proportionate CAF-aligned controls and report significant incidents, regardless of who owns them or what workloads they host.
New requirements for regulated organisations
Incident reporting processes
There could be stricter timelines or broader definitions of what counts as a reportable incident. This might nudge organisations to formalise detection, triage, and escalation procedures.
The Government is proposing to introduce a new two-stage incident reporting process. This would include an initial notification which would be submitted within 24 hours of becoming aware of a significant incident, followed by a full incident report which should be submitted within 72 hours of the same.
Supply chain assurance requirements
Supply chains for the UK's most critical services are becoming increasingly complex and present new and serious vulnerabilities for cyber-attacks. The recent Synnovis ransomware attacks on the NHS[11] exemplify the danger posed by attacks against the supply chains of important services and organisations. This is concerning when reflecting on the latest Cyber Security Breaches survey conducted by DSIT, which highlights that fewer than 25% of large businesses review their supply chain risks[12].
Despite these risks, the UK’s legacy cybersecurity regulatory regime does not explicitly cover supply chain risk management. The UK instead relies on supporting and non-statutory guidance to close this gap, such as the NCSC’s Cyber Assessment Framework (CAF)[13].
The CSRB policy statement acts on this regulatory shortcoming and recognises that “a single supplier’s disruption can have far-reaching impacts on the delivery of essential or digital services”[14].
To address this, the Bill would make in-scope organisations (OES and RDPS) directly accountable for the cybersecurity of their supply chains. Secondary legislation would spell out these duties in detail, ensuring that OES and RDSPs systematically assess and mitigate third-party cyber risks.
Updated and strengthened security requirements
By placing the CAF into a firmer footing and backing it with a statutory Code of Practice, the Government is setting clearer expectations about government expectations on technical standards and methods organisations will need to follow to prove their resilience.
How Darktrace can help support affected organizations
Demonstrate resilience
Darktrace’s Self-Learning AITM continuously monitors your digital estate across cloud, network, OT, email, and endpoint to detect, investigate, and autonomously respond to emerging threats in real time. This persistent visibility and defense posture helps organizations demonstrate cyber resilience to regulators with confidence.
Streamline incident reporting and compliance
Darktrace surfaces clear alerts and automated investigation reports, complete with timeline views and root cause analysis. These insights reduce the time and complexity of regulatory incident reporting and support internal compliance workflows with auditable, AI-generated evidence.
Improve supply chain visibility
With full visibility across connected systems and third-party activity, Darktrace detects early indicators of lateral movement, account compromise, and unusual behavior stemming from vendor or partner access, reducing the risk of supply chain-originated cyber-attacks.
Ensure MSPs can meet new standards
For managed service providers, Darktrace offers native multi-tenant support and autonomous threat response that can be embedded directly into customer environments. This ensures consistent, scalable security standards across clients—helping MSPs address increasing regulatory obligations.
Unpacking ClickFix: Darktrace’s detection of a prolific social engineering tactic
What is ClickFix and how does it work?
Amid heightened security awareness, threat actors continue to seek stealthy methods to infiltrate target networks, often finding the human end user to be the most vulnerable and easily exploited entry point.
ClickFix baiting is an exploitation of the end user, making use of social engineering techniques masquerading as error messages or routine verification processes, that can result in malicious code execution.
Since March 2024, the simplicity of this technique has drawn attention from a range of threat actors, from individual cybercriminals to Advanced Persistent Threat (APT) groups such as APT28 and MuddyWater, linked to Russia and Iran respectively, introducing security threats on a broader scale [1]. ClickFix campaigns have been observed affecting organizations in across multiple industries, including healthcare, hospitality, automotive and government [2][3].
Actors carrying out these targeted attacks typically utilize similar techniques, tools and procedures (TTPs) to gain initial access. These include spear phishing attacks, drive-by compromises, or exploiting trust in familiar online platforms, such as GitHub, to deliver malicious payloads [2][3]. Often, a hidden link within an email or malvertisements on compromised legitimate websites redirect the end user to a malicious URL [4]. These take the form of ‘Fix It’ or fake CAPTCHA prompts [4].
From there, users are misled into believing they are completing a human verification step, registering a device, or fixing a non-existent issue such as a webpage display error. As a result, they are guided through a three-step process that ultimately enables the execution of malicious PowerShell commands:
Open a Windows Run dialog box [press Windows Key + R]
Automatically or manually copy and paste a malicious PowerShell command into the terminal [press CTRL+V]
And run the prompt [press ‘Enter’] [2]
Once the malicious PowerShell command is executed, threat actors then establish command and control (C2) communication within the targeted environment before moving laterally through the network with the intent of obtaining and stealing sensitive data [4]. Malicious payloads associated with various malware families, such as XWorm, Lumma, and AsyncRAT, are often deployed [2][3].
Based on investigations conducted by Darktrace’s Threat Research team in early 2025, this blog highlights Darktrace’s capability to detect ClickFix baiting activity following initial access.
Darktrace’s coverage of a ClickFix attack chain
Darktrace identified multiple ClickFix attacks across customer environments in both Europe, the Middle East, and Africa (EMEA) and the United States. The following incident details a specific attack on a customer network that occurred on April 9, 2025.
Although the initial access phase of this specific attack occurred outside Darktrace’s visibility, other affected networks showed compromise beginning with phishing emails or fake CAPTCHA prompts that led users to execute malicious PowerShell commands.
Darktrace’s visibility into the compromise began when the threat actor initiated external communication with their C2 infrastructure, with Darktrace / NETWORK detecting the use of a new PowerShell user agent, indicating an attempt at remote code execution.
Figure 1: Darktrace / NETWORK's detection of a device making an HTTP connection with new PowerShell user agent, indicating PowerShell abuse for C2 communications.
Download of Malicious Files for Lateral Movement
A few minutes later, the compromised device was observed downloading a numerically named file. Numeric files like this are often intentionally nondescript and associated with malware. In this case, the file name adhered to a specific pattern, matching the regular expression: /174(\d){7}/. Further investigation into the file revealed that it contained additional malicious code designed to further exploit remote services and gather device information.
Figure 2: Darktrace / NETWORK's detection of a numeric file, one minute after the new PowerShell User Agent alert.
The file contained a script that sent system information to a specified IP address using an HTTP POST request, which also processed the response. This process was verified through packet capture (PCAP) analysis conducted by the Darktrace Threat Research team.
By analyzing the body content of the HTTP GET request, it was observed that the command converts the current time to Unix epoch time format (i.e., 9 April 2025 13:26:40 GMT), resulting in an additional numeric file observed in the URI: /1744205200.
Figure 3: PCAP highlighting the HTTP GET request that sends information to the specific IP, 193.36.38[.]237, which then generates another numeric file titled per the current time.
Across Darktrace’s investigations into other customers' affected by ClickFix campaigns, both internal information discovery events and further execution of malicious code were observed.
Data Exfiltration
By following the HTTP stream in the same PCAP, the Darktrace Threat Research Team assessed the activity as indicative of data exfiltration involving system and device information to the same command-and-control (C2) endpoint, , 193.36.38[.]237. This endpoint was flagged as malicious by multiple open-source intelligence (OSINT) vendors [5].
Figure 4: PCAP highlighting HTTP POST connection with the numeric file per the URI /1744205200 that indicates data exfiltration to 193.36.38[.]237.
Further analysis of Darktrace’s Advanced Search logs showed that the attacker’s malicious code scanned for internal system information, which was then sent to a C2 server via an HTTP POST request, indicating data exfiltration
Figure 5: Advanced Search further highlights Darktrace's observation of the HTTP POST request, with the second numeric file representing data exfiltration.
Actions on objectives
Around ten minutes after the initial C2 communications, the compromised device was observed connecting to an additional rare endpoint, 188.34.195[.]44. Further analysis of this endpoint confirmed its association with ClickFix campaigns, with several OSINT vendors linking it to previously reported attacks [6].
In the final HTTP POST request made by the device, Darktrace detected a file at the URI /init1234 in the connection logs to the malicious endpoint 188.34.195[.]44, likely depicting the successful completion of the attack’s objective, automated data egress to a ClickFix C2 server.
Darktrace / NETWORK grouped together the observed indicators of compromise (IoCs) on the compromised device and triggered an Enhanced Monitoring model alert, a high-priority detection model designed to identify activity indicative of the early stages of an attack. These models are monitored and triaged 24/7 by Darktrace’s Security Operations Center (SOC) as part of the Managed Threat Detection service, ensuring customers are promptly notified of malicious activity as soon as it emerges.
Figure 6: Darktrace correlated the separate malicious connections that pertained to a single campaign.
Darktrace Autonomous Response
In the incident outlined above, Darktrace was not configured in Autonomous Response mode. As a result, while actions to block specific connections were suggested, they had to be manually implemented by the customer’s security team. Due to the speed of the attack, this need for manual intervention allowed the threat to escalate without interruption.
However, in a different example, Autonomous Response was fully enabled, allowing Darktrace to immediately block connections to the malicious endpoint (138.199.156[.]22) just one second after the initial connection in which a numerically named file was downloaded [7].
Figure 7: Darktrace Autonomous Response blocked connections to a suspicious endpoint following the observation of the numeric file download.
This customer was also subscribed to our Managed Detection and Response service, Darktrace’s SOC extended a ‘Quarantine Device’ action that had already been autonomously applied in order to buy their security team additional time for remediation.
Figure 8: Autonomous Response blocked connections to malicious endpoints, including 138.199.156[.]22, 185.250.151[.]155, and rkuagqnmnypetvf[.]top, and also quarantined the affected device. These actions were later manually reinforced by the Darktrace SOC.
Conclusion
ClickFix baiting is a widely used tactic in which threat actors exploit human error to bypass security defenses. By tricking end point users into performing seemingly harmless, everyday actions, attackers gain initial access to systems where they can access and exfiltrate sensitive data.
Darktrace’s anomaly-based approach to threat detection identifies early indicators of targeted attacks without relying on prior knowledge or IoCs. By continuously learning each device’s unique pattern of life, Darktrace detects subtle deviations that may signal a compromise. In this case, Darktrace's Autonomous Response, when operating in a fully autonomous mode, was able to swiftly contain the threat before it could progress further along the attack lifecycle.
Credit to Keanna Grelicha (Cyber Analyst) and Jennifer Beckett (Cyber Analyst)
Appendices
NETWORK Models
Device / New PowerShell User Agent
Anomalous Connection / New User Agent to IP Without Hostname
Anomalous Connection / Posting HTTP to IP Without Hostname
Anomalous Connection / Powershell to Rare External
Device / Suspicious Domain
Device / New User Agent and New IP
Anomalous File / New User Agent Followed By Numeric File Download (Enhanced Monitoring Model)
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![PCAP highlighting the HTTP GET request that sends information to the specific IP, 193.36.38[.]237, which then generates another numeric file titled per the current time.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/684068fac1b4368f672c17cc_Screenshot%202025-06-04%20at%208.40.32%E2%80%AFAM.png)
![PCAP highlighting HTTP POST connection with the numeric file per the URI /1744205200 that indicates data exfiltration to 193.36.38[.]237.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6840694509d92b6220ccf5f1_Screenshot%202025-06-04%20at%208.41.48%E2%80%AFAM.png)
![Autonomous Response blocked connections to malicious endpoints, including 138.199.156[.]22, 185.250.151[.]155, and rkuagqnmnypetvf[.]top, and also quarantined the affected device. These actions were later manually reinforced by the Darktrace SOC.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/68406a1f723c9d6fda9c5268_Screenshot%202025-06-04%20at%208.45.23%E2%80%AFAM.png)