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
Max Heinemeyer
Global Field CISO
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Feb 2018
The algorithms made famous by Conficker almost a decade ago are continuing to frustrate the security community.
A function of some advanced malware, Domain Generating Algorithms (DGA) rapidly generate new domains as a means of evading security personnel. This process is known as ‘domain fluxing’ and provides an alternative means of communication with the attacker’s command-and-control servers. They are very difficult to detect using a traditional security approach.
Darktrace’s AI and machine learning are designed to detect threats without any pre-existing knowledge of attacker targets, tools, or capabilities. While traditional security tools depend on specific Indicators of Compromise to identify malicious activity, Darktrace instead focuses on behavioral changes that may point to an active compromise. Detection of Domain Generating Algorithms is just one example of Darktrace’s ability to pinpoint attacker C2 communications through the identification of behavioral anomalies.
DGA identification in action
Darktrace recently saw an employee of a healthcare company connecting a personal laptop to the corporate network. The employee was asked by another member of the organization to troubleshoot the laptop as a favor. Unbeknown to the employee, and despite the fact that anti-virus was installed, the laptop was compromised by an unknown strain of malware.
On joining the network, the compromised laptop made DNS queries for domains that Darktrace classified as 100% rare for the environment. These domains appeared to be dynamically generated as they were all between 25 to 30 characters long and used multiple top-level domains. Darktrace immediately triggered a high-scoring domain fluxing alert due to the sudden increase in failed DNS requests for abnormal domains.
Additional domain fluxing alerts were triggered within 30 minutes of the device joining the network. The only reason that this highly suspicious activity was allowed to persist for that period of time was that the security administrator was at lunch.
A sample of Darktrace network logs showing failed DNS requests for DGA domains.
Event logs showing domain fluxing identification within 14 seconds of the device joining the network.
Rapid containment
The security administrator was informed of the situation on his return and immediately performed incident triage with Darktrace. The administrator was able to rapidly assess the device’s connection history using Darktrace’s native filters that are designed to detect scanning, lateral movement, C2 communications, and egress. He then identified the location of the compromised laptop, disabled its internet access, and physically removed the device from the network.
The total time from initial connection to identification, containment, and removal of the compromised, rogue device was approximately 67 minutes. The administrator left the following comment for the Darktrace analyst team:
Darktrace Threat Visualizer shows multiple domain fluxing model breaches as a result of a high volume of failed DNS requests for suspicious, dynamically-generated domains.
Closing thoughts
Darktrace’s AI approach focuses on identifying anomalies in evolving patterns of behavior. Although the laptop was new to the network, no other device was seen making a high volume of failed DNS requests for similar DGA domains. Darktrace immediately identified this activity as anomalous and generated an alert within 14 seconds of the device joining the network.
By employing Darktrace, a single analyst was able to discover and assess a compromised, rogue device operating within the network environment in just over an hour. What’s more, with Antigena (Darktrace’s autonomous response solution) in place, all suspicious behaviors would have been temporarily suspended, in real time. Alternatively, the administrator could have manually authorized Antigena’s proposed actions via the Darktrace Mobile App.
No extensive analysis of distributed log files, PCAPs, or other security tools. No prior knowledge of the attacker’s infrastructure or the malware. Darktrace AI identified DGA domains that were being produced on the fly, without help. That’s the level our security technology must perform at if we are to keep on top of all the new tech in the modern attacker’s toolkit.
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.
Salty Much: Darktrace’s view on a recent Salt Typhoon intrusion
What is Salt Typhoon?
Salt Typhoon represents one of the most persistent and sophisticated cyber threats targeting global critical infrastructure today. Believed to be linked to state-sponsored actors from the People’s Republic of China (PRC), this advanced persistent threat (APT) group has executed a series of high-impact campaigns against telecommunications providers, energy networks, and government systems—most notably across the United States.
Active since at least 2019, the group—also tracked as Earth Estries, GhostEmperor, and UNC2286—has demonstrated advanced capabilities in exploiting edge devices, maintaining deep persistence, and exfiltrating sensitive data across more than 80 countries. While much of the public reporting has focused on U.S. targets, Salt Typhoon’s operations have extended into Europe, the Middle East, and Africa (EMEA) where it has targeted telecoms, government entities, and technology firms. Its use of custom malware and exploitation of high-impact vulnerabilities (e.g., Ivanti, Fortinet, Cisco) underscores the strategic nature of its campaigns, which blend intelligence collection with geopolitical influence [1].
Leveraging zero-day exploits, obfuscation techniques, and lateral movement strategies, Salt Typhoon has demonstrated an alarming ability to evade detection and maintain long-term access to sensitive environments. The group’s operations have exposed lawful intercept systems, compromised metadata for millions of users, and disrupted essential services, prompting coordinated responses from intelligence agencies and private-sector partners worldwide. As organizations reassess their threat models, Salt Typhoon serves as a stark reminder of the evolving nature of nation-state cyber operations and the urgent need for proactive defense strategies.
Darktrace’s coverage
In this case, Darktrace observed activity in a European telecommunications organisation consistent with Salt Typhoon’s known tactics, techniques and procedures (TTPs), including dynamic-link library (DLL) sideloading and abuse of legitimate software for stealth and execution.
Initial access
The intrusion likely began with exploitation of a Citrix NetScaler Gateway appliance in the first week of July 2025. From there, the actor pivoted to Citrix Virtual Delivery Agent (VDA) hosts in the client’s Machine Creation Services (MCS) subnet. Initial access activities in the intrusion originated from an endpoint potentially associated with the SoftEther VPN service, suggesting infrastructure obfuscation from the outset.
Tooling
Darktrace subsequently observed the threat actor delivering a backdoor assessed with high confidence to be SNAPPYBEE (also known as Deed RAT) [2][3] to multiple Citrix VDA hosts. The backdoor was delivered to these internal endpoints as a DLL alongside legitimate executable files for antivirus software such as Norton Antivirus, Bkav Antivirus, and IObit Malware Fighter. This pattern of activity indicates that the attacker relied on DLL side-loading via legitimate antivirus software to execute their payloads. Salt Typhoon and similar groups have a history of employing this technique [4][5], enabling them to execute payloads under the guise of trusted software and bypassing traditional security controls.
Command-and-Control (C2)
The backdoor delivered by the threat actor leveraged LightNode VPS endpoints for C2, communicating over both HTTP and an unidentified TCP-based protocol. This dual-channel setup is consistent with Salt Typhoon’s known use of non-standard and layered protocols to evade detection. The HTTP communications displayed by the backdoor included POST requests with an Internet Explorer User-Agent header and Target URI patterns such as “/17ABE7F017ABE7F0”. One of the C2 hosts contacted by compromised endpoints was aar.gandhibludtric[.]com (38.54.63[.]75), a domain recently linked to Salt Typhoon [6].
Detection timeline
Darktrace produced high confidence detections in response to the early stages of the intrusion, with both the initial tooling and C2 activities being strongly covered by both investigations by Darktrace Cyber AI AnalystTM investigations and Darktrace models. Despite the sophistication of the threat actor, the intrusion activity identified and remediated before escalating beyond these early stages of the attack, with Darktrace’s timely high-confidence detections likely playing a key role in neutralizing the threat.
Cyber AI Analyst observations
Darktrace’s Cyber AI Analyst autonomously investigated the model alerts generated by Darktrace during the early stages of the intrusion. Through its investigations, Cyber AI Analyst discovered the initial tooling and C2 events and pieced them together into unified incidents representing the attacker’s progression.
Figure 1: Cyber AI Analyst weaved together separate events from the intrusion into broader incidents summarizing the attacker’s progression.
Conclusion
Based on overlaps in TTPs, staging patterns, infrastructure, and malware, Darktrace assesses with moderate confidence that the observed activity was consistent with Salt Typhoon/Earth Estries (ALA GhostEmperor/UNC2286). Salt Typhoon continues to challenge defenders with its stealth, persistence, and abuse of legitimate tools. As attackers increasingly blend into normal operations, detecting behavioral anomalies becomes essential for identifying subtle deviations and correlating disparate signals. The evolving nature of Salt Typhoon’s tradecraft, and its ability to repurpose trusted software and infrastructure, ensures it will remain difficult to detect using conventional methods alone. This intrusion highlights the importance of proactive defense, where anomaly-based detections, not just signature matching, play a critical role in surfacing early-stage activity.
Credit to Nathaniel Jones (VP, Security & AI Strategy, FCISO), Sam Lister (Specialist Security Researcher), Emma Foulger (Global Threat Research Operations Lead), Adam Potter (Senior Cyber Analyst)
Edited by Ryan Traill (Analyst Content Lead)
Appendices
Indicators of Compromise (IoCs)
IoC-Type-Description + Confidence
89.31.121[.]101 – IP Address – Possible C2 server
hxxp://89.31.121[.]101:443/WINMM.dll - URI – Likely SNAPPYBEE download
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.
How a Major Civil Engineering Company Reduced MTTR across Network, Email and the Cloud with Darktrace
Asking more of the information security team
“What more can we be doing to secure the company?” is a great question for any cyber professional to hear from their Board of Directors. After successfully defeating a series of attacks and seeing the potential for AI tools to supercharge incoming threats, a UK-based civil engineering company’s security team had the answer: Darktrace.
“When things are coming at you at machine speed, you need machine speed to fight it off – it’s as simple as that,” said their Information Security Manager. “There were incidents where it took us a few hours to get to the bottom of what was going on. Darktrace changed that.”
Prevention was also the best cure. A peer organization in the same sector was still in business continuity measures 18 months after an attack, and the security team did not want to risk that level of business disruption.
Legacy tools were not meeting the team’s desired speed or accuracy
The company’s native SaaS email platform took between two and 14 days to alert on suspicious emails, with another email security tool flagging malicious emails after up to 24 days. After receiving an alert, responses often took a couple of days to coordinate. The team was losing precious time.
Beyond long detection and response times, the old email security platform was no longer performing: 19% of incoming spam was missed. Of even more concern: 6% of phishing emails reached users’ inboxes, and malware and ransomware email was also still getting through, with 0.3% of such email-borne payloads reaching user inboxes.
Choosing Darktrace
“When evaluating tools in 2023, only Darktrace had what I was looking for: an existing, mature, AI-based cybersecurity solution. ChatGPT had just come out and a lot of companies were saying ‘AI this’ and ‘AI that’. Then you’d take a look, and it was all rules- and cases-based, not AI at all,” their Information Security Manager.
The team knew that, with AI-enabled attacks on the horizon, a cybersecurity company that had already built, fielded, and matured an AI-powered cyber defense would give the security team the ability to fend off machine-speed attacks at the same pace as the attackers.
Darktrace accomplishes this with multi-layered AI that learns each organization’s normal business operations. With this detailed level of understanding, Darktrace’s Self-Learning AI can recognize unusual activity that may indicate a cyber-attack, and works to neutralize the threat with precise response actions. And it does this all at machine speed and with minimal disruption.
On the morning the team was due to present its findings, the session was cancelled – for a good reason. The Board didn’t feel further discussion was necessary because the case for Darktrace was so conclusive. The CEO described the Darktrace option as ‘an insurance policy we can’t do without’.
Saving time with Darktrace / EMAIL
Darktrace / EMAIL reduced the discovery, alert, and response process from days or weeks to seconds .
Darktrace / EMAIL automates what was originally a time-consuming and repetitive process. The team has recovered between eight and 10 working hours a week by automating much of this process using / EMAIL.
Today, Darktrace / EMAIL prevents phishing emails from reaching employees’ inboxes. The volume of hostile and unsolicited email fell to a third of its original level after Darktrace / EMAIL was set up.
Further savings with Darktrace / NETWORK and Darktrace / IDENTITY
Since its success with Darktrace / EMAIL, the company adopted two more products from the Darktrace ActiveAI Security Platform – Darktrace / NETWORK and Darktrace / IDENTITY.
These have further contributed to cost savings. An initial plan to build a 24/7 SOC would have required hiring and retaining six additional analysts, rather than the two that currently use Darktrace, costing an additional £220,000 per year in salary. With Darktrace, the existing analysts have the tools needed to become more effective and impactful.
An additional benefit: Darktrace adoption has lowered the company’s cyber insurance premiums. The security team can reallocate this budget to proactive projects.
Detection of novel threats provides reassurance
Darktrace’s unique approach to cybersecurity added a key benefit. The team’s previous tool took a rules-based approach – which was only good if the next attack featured the same characteristics as the ones on which the tool was trained.
“Darktrace looks for anomalous behavior, and we needed something that detected and responded based on use cases, not rules that might be out of date or too prescriptive,” their Information Security Manager. “Our existing provider could take a couple of days to update rules and signatures, and in this game, speed is of the essence. Darktrace just does everything we need - without delay.”
Where rules-based tools must wait for a threat to emerge before beginning to detect and respond to it, Darktrace identifies and protects against unknown and novel threats, speeding identification, response, and recovery, minimizing business disruption as a result.
Looking to the future
With Darktrace in place, the UK-based civil engineering company team has reallocated time and resources usually spent on detection and alerting to now tackle more sophisticated, strategic challenges. Darktrace has also equipped the team with far better and more regularly updated visibility into potential vulnerabilities.
“One thing that frustrates me a little is penetration testing; our ISO accreditation mandates a penetration test at least once a year, but the results could be out of date the next day,” their Information Security Manager. “Darktrace / Proactive Exposure Management will give me that view in real time – we can run it daily if needed - and that’s going to be a really effective workbench for my team.”
As the company looks to further develop its security posture, Darktrace remains poised to evolve alongside its partner.
