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February 27, 2025

New Threat on the Prowl: Investigating Lynx Ransomware

Lynx ransomware, emerging in 2024, targets finance, architecture, and manufacturing sectors with phishing and double extortion. Read on for Darktrace's findings.
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
Justin Torres
Cyber Analyst
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27
Feb 2025

What is Lynx ransomware?

In mid-2024, a new ransomware actor named Lynx emerged in the threat landscape. This Ransomware-as-a-Service (RaaS) strain is known to target organizations in the finance, architecture, and manufacturing sectors [1] [2]. However, Darktrace’s Threat Research teams also identified Lynx incidents affecting energy and retail organizations in the Middle East and Asia-Pacific (APAC) regions. Despite being a relatively new actor, Lynx’s malware shares large portions of its source code with the INC ransomware variant, suggesting that the group may have acquired and repurposed the readily available INC code to develop its own strain [2].

What techniques does Lynx ransomware group use?

Lynx employs several common attack vectors, including phishing emails which result in the download and installation of ransomware onto systems upon user interaction. The group poses a sophisticated double extortion threat to organizations, exfiltrating sensitive data prior to encryption [1]. This tactic allows threat actors to pressure their targets by threatening to release sensitive information publicly or sell it if the ransom is not paid. The group has also been known to gradually release small batches of sensitive information (i.e., “drip” data) to increase pressure.

Once executed, the malware encrypts files and appends the extension ‘.LYNX’ to all encrypted files. It eventually drops a Base64 encoded text file as a ransom note (i.e., README.txt) [1]. Should initial file encryption attempts fail, the operators have been known to employ privilege escalation techniques to ensure full impact [2].

In the Annual Threat Report 2024, Darktrace’s Threat Research team identified Lynx ransomware as one of the top five most significant threats, impacting both its customers and the broader threat landscape.

Darktrace Coverage of Lynx Ransomware

In cases of Lynx ransomware observed across the Darktrace customer base, Darktrace / NETWORK identified and suggested Autonomous Response actions to contain network compromises from the onset of activity.  

Detection of lateral movement

One such Lynx compromise occurred in December 2024 when Darktrace observed multiple indicators of lateral movement on a customer network. The lateral movement activity started with a high volume of attempted binds to the service control endpoint of various destination devices, suggesting SMB file share enumeration. This activity also included repeated attempts to establish internal connections over destination port 445, as well as other privileged ports. Spikes in failed internal connectivity, such as those exhibited by the device in question, can indicate network scanning. Elements of the internal connectivity also suggested the use of the attack and reconnaissance tool, Nmap.

Indicators of compromised administrative credentials

Although an initial access point could not be confirmed, the widespread use of administrative credentials throughout the lateral movement process demonstrated the likely compromise of such privileged usernames and passwords. The operators of the malware frequently used both 'admin' and 'administrator' credentials throughout the incident, suggesting that attackers may have leveraged compromised default administrative credentials to gain access and escalate privileges. These credentials were observed on numerous devices across the network, triggering Darktrace models that detect unusual use of administrative usernames via methods like NTLM and Kerberos.

Data exfiltration

The lateral movement and reconnaissance behavior was then followed by unusual internal and external data transfers. One such device exhibited an unusual spike in internal data download activity, downloading around 150 GiB over port 3260 from internal network devices. The device then proceeded to upload large volumes of data to the external AWS S3 storage bucket: wt-prod-euwest1-storm.s3.eu-west-1.amazonaws[.]com. Usage of external cloud storage providers is a common tactic to avoid detection of exfiltration, given the added level of legitimacy afforded by cloud service provider domains.

Furthermore, Darktrace observed the device exhibiting behavior suggesting the use of the remote management tool AnyDesk when it made outbound TCP connections to hostnames such as:

relay-48ce591e[.]net[.]anydesk[.]com

relay-c9990d24[.]net[.]anydesk[.]com

relay-da1ad7b4[.]net[.]anydesk[.]com

Tools like AnyDesk can be used for legitimate administrative purposes. However, such tools are also commonly leveraged by threat actors to enable remote access and further compromise activity. The activity observed from the noted device during this time suggests the tool was used by the ransomware operators to advance their compromise goals.

The observed activity culminated in the encryption of thousands of files with the '.Lynx' extension. Darktrace detected devices performing uncommon SMB write and move operations on the drives of destination network devices, featuring the appending of the Lynx extension to local host files. Darktrace also identified similar levels of SMB read and write sizes originating from certain devices. Parallel volumes of SMB read and write activity strongly suggest encryption, as the malware opens, reads, and then encrypts local files on the hosted SMB disk share. This encryption activity frequently highlighted the use of the seemingly-default credential: "Administrator".

In this instance, Darktrace’s Autonomous Response capability was configured to only take action upon human confirmation, meaning the customer’s security team had to manually apply any suggested actions. Had the deployment been fully autonomous, Darktrace would have blocked connectivity to and from the affected devices, giving the customer additional time to contain the attack and enforce existing network behavior patterns while the IT team responded accordingly.

Conclusion

As reported by Darktrace’s Threat Research team in the Annual Threat Report 2024, both new and old ransomware strains were prominent across the threat landscape last year. Due to the continually improving security postures of organizations, ransomware actors are forced to constantly evolve and adopt new tactics to successfully carry out their attacks.

The Lynx group’s use of INC source code, for example, suggests a growing accessibility for threat actors to launch new ransomware strains based on existing code – reducing the cost, resources, and expertise required to build new malware and carry out an attack. This decreased barrier to entry will surely lead to an increased number of ransomware incidents, with attacks not being limited to experienced threat actors.

While Darktrace expects ransomware strains like Lynx to remain prominent in the threat landscape in 2025 and beyond, Darktrace’s ability to identify and respond to emerging ransomware incidents – as demonstrated here – ensures that customers can safeguard their networks and resume normal business operations as quickly as possible, even in an increasingly complex threat landscape.

Credit to Justin Torres (Senior Cyber Analyst) and Adam Potter (Senior Cyber Analyst).

[related-resource]

Appendices

References

1.     https://unit42.paloaltonetworks.com/inc-ransomware-rebrand-to-lynx/

2.     https://cybersecsentinel.com/lynx-ransomware-strikes-new-targets-unveiling-advanced-encryption-techniques/

Autonomous Response Model Alerts

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

·      Antigena::Network::Insider Threat::Antigena Active Threat SMB Write Block

·      Antigena::Network::Significant Anomaly::Antigena Enhanced Monitoring from Client Block

·      Antigena::Network::Significant Anomaly::Antigena Significant Anomaly from Client Block

·      Antigena::Network::Insider Threat::Antigena Network Scan Block

·      Antigena::Network::Insider Threat::Antigena Internal Anomalous File Activity

·      Antigena::Network::Insider Threat::Antigena Unusual Privileged User Activities Block

·      Antigena::Network::Insider Threat::Antigena Unusual Privileged User Activities Pattern of Life Block

·      Antigena::Network::Insider Threat::Antigena Large Data Volume Outbound Block

Darktrace / NETWORK Model Alerts

·      Device::Multiple Lateral Movement Model Alerts

·      Device::Suspicious Network Scan Activity

·      Anomalous File::Internal::Additional Extension Appended to SMB File

·      Device::SMB Lateral Movement

·      Compliance::SMB Drive Write

·      Compromise::Ransomware::Suspicious SMB Activity

·      Anomalous File::Internal::Unusual SMB Script Write

·      Device::Network Scan

·      Device::Suspicious SMB Scanning Activity

·      Device::RDP Scan

·      Unusual Activity::Anomalous SMB Move & Write

·      Anomalous Connection::Sustained MIME Type Conversion

·      Compromise::Ransomware::SMB Reads then Writes with Additional Extensions

·      Unusual Activity::Sustained Anomalous SMB Activity

·      Device::ICMP Address Scan

·      Compromise::Ransomware::Ransom or Offensive Words Written to SMB

·      Anomalous Connection::Suspicious Read Write Ratio

·      Anomalous File::Internal::Masqueraded Executable SMB Write

·      Compliance::Possible Unencrypted Password File On Server

·      User::New Admin Credentials on Client

·      Compliance::Remote Management Tool On Server

·      User::New Admin Credentials on Server

·      Anomalous Connection::Unusual Admin RDP Session

·      Anomalous Connection::Download and Upload

·      Anomalous Connection::Uncommon 1 GiB Outbound

·      Unusual Activity::Unusual File Storage Data Transfer

List of IoCs

IoC - Type - Description + Confidence

- ‘. LYNX’ -  File Extension -  Lynx Ransomware file extension appended to encrypted files

MITRE ATT&CK Mapping  

(Technique Name - Tactic - ID - Sub-Technique of)

Taint Shared Content - LATERAL MOVEMENT - T1080

Data Encrypted for - Impact - IMPACT T1486

Rename System Utilities - DEFENSE EVASION - T1036.003 - T1036

Get the latest insights on emerging cyber threats

This report explores the latest trends shaping the cybersecurity landscape and what defenders need to know in 2025.

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
Justin Torres
Cyber Analyst

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March 11, 2026

NetSupport RAT: How Legitimate Tools Can Be as Damaging as Malware

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What is NetSupport Manager?

NetSupport Manager is a legitimate IT tool used by system administrators for remote support, monitoring, and management. In use since 1989, NetSupport Manager enables users to remotely access and navigate systems across different platforms and operating systems [1].

What is NetSupport RAT?

Although NetSupport Manager is a legitimate tool that can be used by IT and security professionals, there has been a rising number of cases in which it is abused to gain unauthorized access to victim systems. This misuse has become so prevalent that, in recent years, security researchers have begun referring to NetSupport as a Remote Access Trojan (RAT), a term typically used for malware that enables a threat actor to remotely access or control an infected device [2][3][4].

NetSupport RAT activity summary

The initial stages of NetSupport RAT infection may vary depending on the source of the initial compromise. Using tactics such as the social engineering tactic ClickFix, threat actors attempt to trick users into inadvertently executing malicious PowerShell commands under the guise of resolving a non-existent issue or completing a fake CAPTCHA verification [5]. Other attack vectors such as phishing emails, fake browser updates, malicious websites, search engine optimization (SEO) poisoning, malvertising and drive-by downloads are also employed to direct users to fraudulent pages and fake reCAPTCHA verification checks, ultimately inducing them to execute malicious PowerShell commands [5][6][7]. This leads to the successful installation of NetSupport Manager on the compromised device, which is often placed in non-standard directories such as AppData, ProgramData, or Downloads [3][8].

Once installed, the adversary is able to gain remote access to the affected machine, monitor user activity, exfiltrate data, communicate with the command-and-control (C2) server, and maintain persistence [5]. External research has also highlighted that post-exploitation of NetSupport RAT has involved the additional download of malicious payloads [2][5].

Attack flow diagram highlighting key events across each phase of the attack phase
Figure 1: Attack flow diagram highlighting key events across each phase of the attack phase [2][5].

Darktrace coverage

In November of 2025, suspicious behavior indicative of the malicious abuse of NetSupport Manager was observed on multiple customers across Europe, the Middle East, and Africa (EMEA) and the Americas (AMS).

While open-source intelligence (OSINT) has reported that, in a recent campaign, a threat actor impersonated government entities to trick users in organizations in the Information Technology, Government and Financial Services sectors in Central Asia into downloading NetSupport Manager [8], approximately a third of Darktrace’s affected customers in November were based in the US while the rest were based in EMEA. This contrast underscores how widely NetSupport Manager is leveraged by threat actors and highlights its accessibility as an initial access tool.  

The Darktrace customers affected were in sectors including Information and Communication, Manufacturing and Arts, entertainment and recreation.

The ClickFix social engineering tactic typically used to distribute the NetSupport RAT is known to target multiple industries, including Technology, Manufacturing and Energy sectors [9]. It also reflects activity observed in the campaign targeting Central Asia, where the Information Technology sector was among those affected [8].

The prevalence of affected Education customers highlights NetSupport’s marketing focus on the Education sector [10]. This suggests that threat actors are also aware of this marketing strategy and have exploited the trust it creates to deploy NetSupport Manager and gain access to their targets’ systems. While the execution of the PowerShell commands that led to the installation of NetSupport Manager falls outside of Darktrace's purview in cases identified, Darktrace was still able to identify a pattern of devices making connections to multiple rare external domains and IP addresses associated with the NetSupport RAT, using a wide range of ports over the HTTP protocol. A full list of associated domains and IP addresses is provided in the Appendices of this blog.

Although OSINT identifies multiple malicious domains and IP addresses as used as C2 servers, signature-based detections of NetSupport RAT indicators of compromise (IoCs) may miss broader activity, as new malicious websites linked to the RAT continue to appear.

Darktrace’s anomaly‑based approach allows it to establish a normal ‘pattern of life’ for each device on a network and identify when behavior deviates from this baseline, enabling the detection of unusual activity even when it does not match known IoCs or tactics, techniques and procedures (TTPs).

In one customer environment in late 2025, Darktrace / NETWORK detected a device initiating new connections to the rare external endpoint, thetavaluemetrics[.]com (74.91.125[.]57), along with the use of a previously unseen user agent, which it recognized as highly unusual for the network.

Darktrace’s detection of HTTP POST requests to a suspicious URI and new user agent usage.
Figure 2: Darktrace’s detection of HTTP POST requests to a suspicious URI and new user agent usage.

Darktrace identified that user agent present in connections to this endpoint was the ‘NetSupport Manager/1.3’, initially suggesting legitimate NetSupport Manager activity. Subsequent investigation, however, revealed that the endpoint was in fact a malicious NetSupportRAT C2 endpoint [12]. Shortly after, Darktrace detected the same device performing HTTP POST requests to the URI fakeurl[.]htm. This pattern of activity is consistent with OSINT reporting that details communication between compromised devices and NetSupport Connectivity Gateways functioning as C2 servers [11].

Conclusion

As seen not only with NetSupport Manager but with any legitimate or open‑source software used by IT and security professionals, the legitimacy of a tool does not prevent it from being abused by threat actors. Open‑source software, especially tools with free or trial versions such as NetSupport Manager, remains readily accessible for malicious use, including network compromise. In an age where remote work is still prevalent, validating any anomalous use of software and remote management tools is essential to reducing opportunities for unauthorized access.

Darktrace’s anomaly‑based detection enables security teams to identify malicious use of legitimate tools, even when clear signatures or indicators of compromise are absent, helping to prevent further impact on a network.


Credit to George Kim (Analyst Consulting Lead – AMS), Anna Gilbertson (Senior Cyber Analyst)

Edited by Ryan Traill (Analyst Content Lead)

Appendices

Darktrace Model Alerts

·       Compromise / Suspicious HTTP and Anomalous Activity

·       Compromise / New User Agent and POST

·       Device / New User Agent

·       Anomalous Connection / New User Agent to IP Without Hostname

·       Anomalous Connection / Posting HTTP to IP Without Hostname

·       Anomalous Connection / Multiple Failed Connections to Rare Endpoint

·       Anomalous Connection / Application Protocol on Uncommon Port

·       Anomalous Connection / Multiple HTTP POSTs to Rare Hostname

·       Compromise / Beaconing Activity To External Rare

·       Compromise / HTTP Beaconing to Rare Destination

·       Compromise / Agent Beacon (Medium Period)

·       Compromise / Agent Beacon (Long Period)

·       Compromise / Quick and Regular Windows HTTP Beaconing

·       Compromise / Sustained TCP Beaconing Activity To Rare Endpoint

·       Compromise / POST and Beacon to Rare External

Indicators of Compromise (IoCs)

Indicator           Type     Description

/fakeurl.htm URI            NetSupportRAT C2 URI

thetavaluemetrics[.]com        Connection hostname              NetSupportRAT C2 Endpoint

westford-systems[.]icu            Connection hostname              NetSupportRAT C2 Endpoint

holonisz[.]com                Connection hostname              NetSupportRAT C2 Endpoint

heaveydutyl[.]com      Connection hostname              NetSupportRAT C2 Endpoint

nsgatetest1[.]digital   Connection hostname              NetSupportRAT C2 Endpoint

finalnovel[.]com            Connection hostname              NetSupportRAT C2 Endpoint

217.91.235[.]17              IP             NetSupportRAT C2 Endpoint

45.94.47[.]224                 IP             NetSupportRAT C2 Endpoint

74.91.125[.]57                 IP             NetSupportRAT C2 Endpoint

88.214.27[.]48                 IP             NetSupportRAT C2 Endpoint

104.21.40[.]75                 IP             NetSupportRAT C2 Endpoint

38.146.28[.]242              IP             NetSupportRAT C2 Endpoint

185.39.19[.]233              IP             NetSupportRAT C2 Endpoint

45.88.79[.]237                 IP             NetSupportRAT C2 Endpoint

141.98.11[.]224              IP             NetSupportRAT C2 Endpoint

88.214.27[.]166              IP             NetSupportRAT C2 Endpoint

107.158.128[.]84          IP             NetSupportRAT C2 Endpoint

87.120.93[.]98                 IP             Rhadamanthys C2 Endpoint

References

  1. https://mspalliance.com/netsupport-debuts-netsupport-24-7/
  2. https://blogs.vmware.com/security/2023/11/netsupport-rat-the-rat-king-returns.html
  3. https://redcanary.com/threat-detection-report/threats/netsupport-manager/
  4. https://www.elastic.co/guide/en/security/8.19/netsupport-manager-execution-from-an-unusual-path.html
  5. https://rewterz.com/threat-advisory/netsupport-rat-delivered-through-spoofed-verification-pages-active-iocs
  6. https://thehackernews.com/2025/11/new-evalusion-clickfix-campaign.html
  7. https://corelight.com/blog/detecting-netsupport-manager-abuse
  8. https://thehackernews.com/2025/11/bloody-wolf-expands-java-based.html
  9. https://unit42.paloaltonetworks.com/preventing-clickfix-attack-vector
  10. https://www.netsupportsoftware.com/education-solutions
  11. https://www.esentire.com/blog/unpacking-netsupport-rat-loaders-delivered-via-clickfix
  12. https://threatfox.abuse.ch/browse/malware/win.netsupportmanager_rat/
  13. https://www.virustotal.com/gui/url/5fe6936a69c786c9ded9f31ed1242c601cd64e1d90cecd8a7bb03182c47906c2

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About the author
George Kim
Analyst Consulting Lead – AMS

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March 5, 2026

Inside Cloud Compromise: Investigating Attacker Activity with Darktrace / Forensic Acquisition & Investigation

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Investigating Cloud Attacks with Forensic Acquisition & Investigation

Darktrace / Forensic Acquisition & Investigation™ is the industry’s first truly automated forensic solution purpose-built for the cloud. This blog will demonstrate how an investigation can be carried out against a compromised cloud server in minutes, rather than hours or days.

The compromised server investigated in this case originates from Darktrace’s Cloudypots system, a global honeypot network designed to observe adversary activity in real time across a wide range of cloud services. Whenever an attacker successfully compromises one of these honeypots, a forensic copy of the virtual server's disk is preserved for later analysis. Using Forensic Acquisition & Investigation, analysts can then investigate further and obtain detailed insights into the compromise including complete attacker timelines and root cause analysis.

Forensic Acquisition & Investigation supports importing artifacts from a variety of sources, including EC2 instances, ECS, S3 buckets, and more. The Cloudypots system produces a raw disk image whenever an attack is detected and stores it in an S3 bucket. This allows the image to be directly imported into Forensic Acquisition & Investigation using the S3 bucket import option.

As Forensic Acquisition & Investigation runs cloud-natively, no additional configuration is required to add a specific S3 bucket. Analysts can browse and acquire forensic assets from any bucket that the configured IAM role is permitted to access. Operators can also add additional IAM credentials, including those from other cloud providers, to extend access across multiple cloud accounts and environments.

Figure 1: Forensic Acquisition & Investigation import screen.

Forensic Acquisition & Investigation then retrieves a copy of the file and automatically begins running the analysis pipeline on the artifact. This pipeline performs a full forensic analysis of the disk and builds a timeline of the activity that took place on the compromised asset. By leveraging Forensic Acquisition & Investigation’s cloud-native analysis system, this process condenses hour of manual work into just minutes.

Successful import of a forensic artifact and initiation of the analysis pipeline.
Figure 2: Successful import of a forensic artifact and initiation of the analysis pipeline.

Once processing is complete, the preserved artifact is visible in the Evidence tab, along with a summary of key information obtained during analysis, such as the compromised asset’s hostname, operating system, cloud provider, and key event count.

The Evidence overview showing the acquired disk image.
Figure 3: The Evidence overview showing the acquired disk image.

Clicking on the “Key events” field in the listing opens the timeline view, automatically filtered to show system- generated alarms.

The timeline provides a chronological record of every event that occurred on the system, derived from multiple sources, including:

  • Parsed log files such as the systemd journal, audit logs, application specific logs, and others.
  • Parsed history files such as .bash_history, allowing executed commands to be shown on the timeline.
  • File-specific events, such as files being created, accessed, modified, or executables being run, etc.

This approach allows timestamped information and events from multiple sources to be aggregated and parsed into a single, concise view, greatly simplifying the data review process.

Alarms are created for specific timeline events that match either a built-in system rule, curated by Darktrace’s Threat Research team or an operator-defined created at the project level. These alarms help quickly filter out noise and highlight on events of interest, such as the creation of a file containing known malware, access to sensitive files like Amazon Web Service (AWS) credentials, suspicious arguments or commands, and more.

 The timeline view filtered to alarm_severity: “1” OR alarm_severity: “3”, showing only events that matched an alarm rule.
Figure 4: The timeline view filtered to alarm_severity: “1” OR alarm_severity: “3”, showing only events that matched an alarm rule.

In this case, several alarms were generated for suspicious Base64 arguments being passed to Selenium. Examining the event data, it appears the attacker spawned a Selenium Grid session with the following payload:

"request.payload": "[Capabilities {browserName: chrome, goog:chromeOptions: {args: [-cimport base64;exec(base64...], binary: /usr/bin/python3, extensions: []}, pageLoadStrategy: normal}]"

This is a common attack vector for Selenium Grid. The chromeOptions object is intended to specify arguments for how Google Chrome should be launched; however, in this case the attacker has abused the binary field to execute the Python3 binary instead of Chrome. Combined with the option to specify command-line arguments, the attacker can use Python3’s -c option to execute arbitrary Python code, in this instance, decoding and executing a Base64 payload.

Selenium’s logs truncate the Arguments field automatically, so an alternate method is required to retrieve the full payload. To do this, the search bar can be used to find all events that occurred around the same time as this flagged event.

Pivoting off the previous event by filtering the timeline to events within the same window using timestamp: [“2026-02-18T09:09:00Z” TO “2026-02-18T09:12:00Z”].
Figure 5: Pivoting off the previous event by filtering the timeline to events within the same window using timestamp: [“2026-02-18T09:09:00Z” TO “2026-02-18T09:12:00Z”].

Scrolling through the search results, an entry from Java’s systemd journal can be identified. This log contains the full, unaltered payload. GCHQ’s CyberChef can then be used to decode the Base64 data into the attacker’s script, which will ultimately be executed.[NJ9]

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About the author
Nathaniel Bill
Malware Research Engineer
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