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July 4, 2024

A Busy Agenda: Darktrace's Detection of Qilin Ransomware as a Service Operator

This blog breaks down how Darktrace detected and analyzed Qilin, a Ransomware-as-a-Service group behind recent high-impact attacks. You’ll see how Qilin affiliates customize attacks with flexible encryption, process termination, and double-extortion techniques, as well as why its cross-platform builds in Rust and Golang make it especially evasive. Darktrace highlights three real-world cases where its AI identified likely Qilin activity across customer environments, offering insights into how behavioral detection can spot novel ransomware before disruption occurs. Readers will gain a clear view of Qilin’s toolkit, tactics, and how self-learning defense adapts to these evolving threats.
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
Alexandra Sentenac
Cyber Analyst
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04
Jul 2024

What is Qilin Ransomware and what's its impact?

Qilin ransomware has recently dominated discussions across the cyber security landscape following its deployment in an attack on Synnovis, a UK-based medical laboratory company. The ransomware attack ultimately affected patient services at multiple National Health Service (NHS) hospitals that rely on Synnovis diagnostic and pathology services. Qilin’s origins, however, date back further to October 2022 when the group was observed seemingly posting leaked data from its first known victim on its Dedicated Leak Site (DLS) under the name Agenda[1].

The Darktrace Threat Research team investigated network artifacts related to Qilin and identified three probable cases of the ransomware across the Darktrace customer base between June 2022 and May 2024.

How Qilin Ransowmare Operates as RaaS

Qilin operates as a Ransomware-as-a-Service (RaaS) that employs double extortion tactics, whereby harvested data is exfiltrated and threatened of publication on the group's DLS, which is hosted on Tor. Qilin ransomware has samples written in both the Golang and Rust programming languages, making it compilable with various operating systems, and is highly customizable.

Techniques Qilin Ransomware uses to avoid detection

When building Qilin ransomware variants to be used on their target(s), affiliates can configure settings such as:

  • Encryption modes (skip-step, percent, or speed)
  • File extensions, directories, or processes to exclude
  • Unique company IDs used as extensions on encrypted files
  • Services or processes to terminate during execution [1] [2].
  • Trend Micro analysts, who were the first to discover Qilin samples in August 2022, when the name "Agenda" was still used in ransom notes, found that each analyzed sample was customized for the intended victims and that "unique company IDs were used as extensions of encrypted files" [3]. This information is configurable from within the Qilin's affiliate panel's 'Targets' section, shown below.

    Qilin's affiliate panel and branding

    The panel's background image features the eponym Chinese legendary chimerical creature Qilin (pronounced “Ke Lin”). Despite this Chinese mythology reference, Russian language was observed being used by a Qilin operator in an underground forum post aimed at hiring affiliates and advertising their RaaS operation[2].

    Figure 1: Qilin ransomware’s affiliate panel.

    Qilin’s affiliate payment model

    Qilin's RaaS program purportedly has an attractive affiliates' payment structure,

    • Affiliates earn 80% of ransom payments under USD 3 million
    • Affiliates earn 85% of ransom payments above USD 3 million [2]

    Publication of stolen data and ransom payment negotiations are purportedly handled by Qilin operators. Qilin affiliates have been known to target companies located around the world and within a variety of industries, including critical sectors such as healthcare and energy.

    Qilin target industries and victims

    As Qilin is a RaaS operation, the choice of targets does not necessarily reflect Qilin operators' intentions, but rather that of its affiliates.  

    Similarly, the tactics, techniques, procedures (TTPs) and indicators of compromise (IoC) identified by Darktrace are associated with the given affiliate deploying Qilin ransomware for their own purpose, rather than TTPs and IoCs of the Qilin group. Likewise, initial vectors of infection may vary from affiliate to affiliate.

    Previous studies show that initial access to networks were gained via spear phishing emails or by leveraging exposed applications and interfaces.

    Differences have been observed in terms of data exfiltration and potential C2 external endpoints, suggesting the below investigations are not all related to the same group or actor(s).

    [related-resource]

    Darktrace’s threat research investigation

    Qlin ransomware attack breakdown

    June 2022: Qilin ransomware attack exploiting VPN and SCCM servers

    Key findings:

    • Initial access: VPN and compromised admin account
    • Lateral movement: SCCM and VMware ESXi hosts
    • Malware observed: SystemBC, Tofsee
    • Ransom notes: Linked to Qilin naming conventions
    • Darktrace visibility: Analysts worked with customer via Ask the Expert (ATE) to expand coverage, revealing unusual scanning, rare external connections, and malware indicators tied to Qilin

    Full story:

    Darktrace first detected an instance of Qilin ransomware back in June 2022, when an attacker was observed successfully accessing a customer’s Virtual Private Network (VPN) and compromising an administrative account, before using RDP to gain access to the customer’s Microsoft System Center Configuration Manager (SCCM) server.

    From there, an attack against the customer's VMware ESXi hosts was launched. Fortunately, a reboot of their virtual machines (VM) caught the attention of the security team who further uncovered that custom profiles had been created and remote scripts executed to change root passwords on their VM hosts. Three accounts were found to have been compromised and three systems encrypted by ransomware.  

    Unfortunately, Darktrace was not configured to monitor the affected subnets at the time of the attack. Despite this, the customer was able to work directly with Darktrace analysts via the Ask the Expert (ATE) service to add the subnets in question to Darktrace’s visibility, allowing it to monitor for any further unusual behavior.

    Once visibility over the compromised SCCM server was established, Darktrace observed:

    • A series of unusual network scanning activities  
    • The use of Kali (a Linux distribution designed for digital forensics and penetration testing).
    • Connections to multiple rare external hosts. Many of which were using the “[.]ru” Top Level Domain (TLD).

    One of the external destinations the server was attempting to connect was found to be related to SystemBC, a malware that turns infected hosts into SOCKS5 proxy bots and provides command-and-control (C2) functionality.

    Additionally, the server was observed making external connections over ports 993 and 143 (typically associated with the use of the Interactive Message Access Protocol (IMAP) to multiple rare external endpoints. This was likely due to the presence of Tofsee malware on the device.

    After the compromise had been contained, Darktrace identified several ransom notes following the naming convention “README-RECOVER-<extension/company_id>.txt”” on the network. This naming convention, as well as the similar “<company_id>-RECOVER-README.txt” have been referenced by open-source intelligence (OSINT) providers as associated with Qilin ransom notes[5] [6] [7].

    April 2023: Manufacturing sector breach with large-scale exfiltration

    Key findings:

    • Initial access & movement: Extensive scanning and lateral movement via SMB, RDP, and WMI
    • Credential abuse: Use of default credentials (admin, administrator)
    • Malware/Indicators: Evidence of Cobalt Strike; suspicious WebDAV user agent and JA3 fingerprint
    • Data exfiltration: ~30 GB stolen via SSL to MEGA cloud storage
    • Darktrace analysis: Detected anomalous SMB and DCE-RPC traffic from domain controller, high-volume RDP activity, and rare external connectivity to IPs tied to command-and-control (C2). Confirmed ransom notes followed Qilin naming conventions.

    Full story:

    The next case of Qilin ransomware observed by Darktrace took place in April 2023 on the network of a customer in the manufacturing sector in APAC. Unfortunately for the customer in this instance, Darktrace's Autonomous Response was not active on their environment and no autonomous actions were taken to contain the compromise.

    Over the course of two days, Darktrace identified a wide range of malicious activity ranging from extensive initial scanning and lateral movement attempts to the writing of ransom notes that followed the aforementioned naming convention (i.e., “README-RECOVER-<extension/company_id>.txt”).

    Darktrace observed two affected devices attempting to move laterally through the SMB, DCE-RPC and RDP network protocols. Default credentials (e.g., UserName, admin, administrator) were also observed in the large volumes of SMB sessions initiated by these devices. One of the target devices of these SMB connections was a domain controller, which was subsequently seen making suspicious WMI requests to multiple devices over DCE-RPC and enumerating SMB shares by binding to the ‘server service’ (srvsvc) named pipe to a high number of internal devices within a short time frame. The domain controller was further detected establishing an anomalously high number of connections to several internal devices, notably using the RDP administrative protocol via a default admin cookie.  

    Repeated connections over the HTTP and SSL protocol to multiple newly observed IPs located in the 184.168.123.0/24 range were observed, indicating C2 connectivity.  WebDAV user agent and a JA3 fingerprint potentially associated with Cobalt Strike were notably observed in these connections. A few hours later, Darktrace detected additional suspicious external connections, this time to IPs associated with the MEGA cloud storage solution. Storage solutions such as MEGA are often abused by attackers to host stolen data post exfiltration. In this case, the endpoints were all rare for the network, suggesting this solution was not commonly used by legitimate users. Around 30 GB of data was exfiltrated over the SSL protocol.

    Darktrace did not observe any encryption-related activity on this customer’s network, suggesting that encryption may have taken place locally or within network segments not monitored by Darktrace.

    May 2024: US enterprise compromise

    Key findings:

    • Initial access & movement: Abuse of administrative and default credentials; lateral movement via DCE-RPC and RDP
    • Malware/Indicators: Suspicious executables (‘a157496.exe’, ‘83b87b2.exe’); abuse of RPC service LSM_API_service
    • Data exfiltration: Large amount of data exfiltrated via FTP and other channels to rare external endpoint (194.165.16[.]13)
    • C2 communications: HTTP/SSL traffic linked to Cobalt Strike, including PowerShell request for sihost64.dll
    • Darktrace analysis: Flagged unusual SMB writes, malicious file transfers, and large-scale exfiltration as highly anomalous. Confirmed widespread encryption activity targeting numerous devices and shares.

    Full story:

    The most recent instance of Qilin observed by Darktrace took place in May 2024 and involved a customer in the US.

    In this case, Darktrace initially detected affected devices using unusual administrative and default credentials. Then Darktrace observed additional Internal systems conducting abnormal activity such as:

    • Making extensive suspicious DCE-RPC requests to a range of internal locations
    • Performing network scanning
    • Making unusual internal RDP connections
    • And transferring suspicious executable files like 'a157496.exe' and '83b87b2.exe'.  

    SMB writes of the file "LSM_API_service" were also observed, activity which was considered 100% unusual by Darktrace; this is an RPC service that can be abused to enumerate logged-in users and steal their tokens. Various repeated connections likely representative of C2 communications were detected via both HTTP and SSL to rare external endpoints linked in OSINT to Cobalt Strike use. During these connections, HTTP GET requests for the following URIs were observed:

    /asdffHTTPS

    /asdfgdf

    /asdfgHTTP

    /download/sihost64.dll

    Notably, this included a GET request a DLL file named "sihost64.dll" from a domain controller using PowerShell.  

    Over 102 GB of data may have been transferred to another previously unseen endpoint, 194.165.16[.]13, via the unencrypted File Transfer Protocol (FTP). Additionally, many non-FTP connections to the endpoint could be observed, over which more than 783 GB of data was exfiltrated. Regarding file encryption activity, a wide range of destination devices and shares were targeted.

    Figure 2: Advanced Search graph displaying the total volume of data transferred over FTP to a malicious IP.

    During investigations, Darktrace’s Threat Research team identified an additional customer, also based in the United States, where similar data exfiltration activity was observed in April 2024. Although no indications of ransomware encryption were detected on the network, multiple similarities were observed with the case discussed just prior. Notably, the same exfiltration IP and protocol (194.165.16[.]13 and FTP, respectively) were identified in both cases. Additional HTTP connectivity was further observed to another IP using a self-signed certificate (i.e., CN=ne[.]com,OU=key operations,O=1000,L=,ST=,C=KM) located within the same ASN (i.e., AS48721 Flyservers S.A.). Some of the URIs seen in the GET requests made to this endpoint were the same as identified in that same previous case.

    Information regarding another device also making repeated connections to the same IP was described in the second event of the same Cyber AI Analyst incident. Following this C2 connectivity, network scanning was observed from a compromised domain controller, followed by additional reconnaissance and lateral movement over the DCE-RPC and SMB protocols. Darktrace again observed SMB writes of the file "LSM_API_service", as in the previous case, activity which was also considered 100% unusual for the network. These similarities suggest the same actor or affiliate may have been responsible for activity observed, even though no encryption was observed in the latter case.

    Figure 3: First event of the Cyber AI Analyst investigation following the compromise activity.

    According to researchers at Microsoft, some of the IoCs observed on both affected accounts are associated with Pistachio Tempest, a threat actor reportedly associated with ransomware distribution. The Microsoft threat actor naming convention uses the term "tempest" to reference criminal organizations with motivations of financial gain that are not associated with high confidence to a known non-nation state or commercial entity. While Pistachio Tempest’s TTPs have changed over time, their key elements still involve ransomware, exfiltration, and extortion. Once they've gained access to an environment, Pistachio Tempest typically utilizes additional tools to complement their use of Cobalt Strike; this includes the use of the SystemBC RAT and the SliverC2 framework, respectively. It has also been reported that Pistacho Tempest has experimented with various RaaS offerings, which recently included Qilin ransomware[4].

    Conclusion

    Qilin is a RaaS group that has gained notoriety recently due to high-profile attacks perpetrated by its affiliates. Despite this, the group likely includes affiliates and actors who were previously associated with other ransomware groups. These individuals bring their own modus operandi and utilize both known and novel TTPs and IoCs that differ from one attack to another.

    Darktrace’s anomaly-based technology is inherently threat-agnostic, treating all RaaS variants equally regardless of the attackers’ tools and infrastructure. Deviations from a device’s ‘learned’ pattern of behavior during an attack enable Darktrace to detect and contain potentially disruptive ransomware attacks.

    [related-resource]

    Credit to: Alexandra Sentenac, Emma Foulger, Justin Torres, Min Kim, Signe Zaharka for their contributions.

    References

    [1] https://www.sentinelone.com/anthology/agenda-qilin/  

    [2] https://www.group-ib.com/blog/qilin-ransomware/

    [3] https://www.trendmicro.com/en_us/research/22/h/new-golang-ransomware-agenda-customizes-attacks.html

    [4] https://www.microsoft.com/en-us/security/security-insider/pistachio-tempest

    [5] https://www.trendmicro.com/en_us/research/22/h/new-golang-ransomware-agenda-customizes-attacks.html

    [6] https://www.bleepingcomputer.com/forums/t/790240/agenda-qilin-ransomware-id-random-10-char;-recover-readmetxt-support/

    [7] https://github.com/threatlabz/ransomware_notes/tree/main/qilin

    Darktrace Model Detections

    Internal Reconnaissance

    Device / Suspicious SMB Scanning Activity

    Device / Network Scan

    Device / RDP Scan

    Device / ICMP Address Scan

    Device / Suspicious Network Scan Activity

    Anomalous Connection / SMB Enumeration

    Device / New or Uncommon WMI Activity

    Device / Attack and Recon Tools

    Lateral Movement

    Device / SMB Session Brute Force (Admin)

    Device / Large Number of Model Breaches from Critical Network Device

    Device / Multiple Lateral Movement Model Breaches

    Anomalous Connection / Unusual Admin RDP Session

    Device / SMB Lateral Movement

    Compliance / SMB Drive Write

    Anomalous Connection / New or Uncommon Service Control

    Anomalous Connection / Anomalous DRSGetNCChanges Operation

    Anomalous Server Activity / Domain Controller Initiated to Client

    User / New Admin Credentials on Client

    C2 Communication

    Anomalous Server Activity / Outgoing from Server

    Anomalous Connection / Multiple Connections to New External TCP Port

    Anomalous Connection / Anomalous SSL without SNI to New External

    Anomalous Connection / Rare External SSL Self-Signed

    Device / Increased External Connectivity

    Unusual Activity / Unusual External Activity

    Compromise / New or Repeated to Unusual SSL Port

    Anomalous Connection / Multiple Failed Connections to Rare Endpoint

    Device / Suspicious Domain

    Device / Increased External Connectivity

    Compromise / Sustained SSL or HTTP Increase

    Compromise / Botnet C2 Behaviour

    Anomalous Connection / POST to PHP on New External Host

    Anomalous Connection / Multiple HTTP POSTs to Rare Hostname

    Anomalous File / EXE from Rare External Location

    Exfiltration

    Unusual Activity / Enhanced Unusual External Data Transfer

    Anomalous Connection / Data Sent to Rare Domain

    Unusual Activity / Unusual External Data Transfer

    Anomalous Connection / Uncommon 1 GiB Outbound

    Unusual Activity / Unusual External Data to New Endpoint

    Compliance / FTP / Unusual Outbound FTP

    File Encryption

    Compromise / Ransomware / Suspicious SMB Activity

    Anomalous Connection / Sustained MIME Type Conversion

    Anomalous File / Internal / Additional Extension Appended to SMB File

    Compromise / Ransomware / Possible Ransom Note Write

    Compromise / Ransomware / Possible Ransom Note Read

    Anomalous Connection / Suspicious Read Write Ratio

    IoC List

    IoC – Type – Description + Confidence

    93.115.25[.]139 IP C2 Server, likely associated with SystemBC

    194.165.16[.]13 IP Probable Exfiltration Server

    91.238.181[.]230 IP C2 Server, likely associated with Cobalt Strike

    ikea0[.]com Hostname C2 Server, likely associated with Cobalt Strike

    lebondogicoin[.]com Hostname C2 Server, likely associated with Cobalt Strike

    184.168.123[.]220 IP Possible C2 Infrastructure

    184.168.123[.]219 IP Possible C2 Infrastructure

    184.168.123[.]236 IP Possible C2 Infrastructure

    184.168.123[.]241 IP Possible C2 Infrastructure

    184.168.123[.]247 IP Possible C2 Infrastructure

    184.168.123[.]251 IP Possible C2 Infrastructure

    184.168.123[.]252 IP Possible C2 Infrastructure

    184.168.123[.]229 IP Possible C2 Infrastructure

    184.168.123[.]246 IP Possible C2 Infrastructure

    184.168.123[.]230 IP Possible C2 Infrastructure

    gfs440n010.userstorage.me ga.co[.]nz Hostname Possible Exfiltration Server. Not inherently malicious; associated with MEGA file storage.

    gfs440n010.userstorage.me ga.co[.]nz Hostname Possible Exfiltration Server. Not inherently malicious; associated with MEGA file storage.

    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
    Alexandra Sentenac
    Cyber Analyst

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    September 3, 2025

    From PowerShell to Payload: Darktrace’s Detection of a Novel Cryptomining Malware

    novel cryptomining detectionDefault blog imageDefault blog image

    What is Cryptojacking?

    Cryptojacking remains one of the most persistent cyber threats in the digital age, showing no signs of slowing down. It involves the unauthorized use of a computer or device’s processing power to mine cryptocurrencies, often without the owner’s consent or knowledge, using cryptojacking scripts or cryptocurrency mining (cryptomining) malware [1].

    Unlike other widespread attacks such as ransomware, which disrupt operations and block access to data, cryptomining malware steals and drains computing and energy resources for mining to reduce attacker’s personal costs and increase “profits” earned from mining [1]. The impact on targeted organizations can be significant, ranging from data privacy concerns and reduced productivity to higher energy bills.

    As cryptocurrency continues to grow in popularity, as seen with the ongoing high valuation of the global cryptocurrency market capitalization (almost USD 4 trillion at time of writing), threat actors will continue to view cryptomining as a profitable venture [2]. As a result, illicit cryptominers are being used to steal processing power via supply chain attacks or browser injections, as seen in a recent cryptojacking campaign using JavaScript [3][4].

    Therefore, security teams should maintain awareness of this ongoing threat, as what is often dismissed as a "compliance issue" can escalate into more severe compromises and lead to prolonged exposure of critical resources.

    While having a security team capable of detecting and analyzing hijacking attempts is essential, emerging threats in today’s landscape often demand more than manual intervention.

    This blog will discuss Darktrace’s successful detection of the malicious activity, the role of Autonomous Response in halting the cryptojacking attack, include novel insights from Darktrace’s threat researchers on the cryptominer payload, showing how the attack chain was initiated through the execution of a PowerShell-based payload.

    Darktrace’s Coverage of Cryptojacking via PowerShell

    In July 2025, Darktrace detected and contained an attempted cryptojacking incident on the network of a customer in the retail and e-commerce industry.

    The threat was detected when a threat actor attempted to use a PowerShell script to download and run NBMiner directly in memory.

    The initial compromise was detected on July 22, when Darktrace / NETWORK observed the use of a new PowerShell user agent during a connection to an external endpoint, indicating an attempt at remote code execution.

    Specifically, the targeted desktop device established a connection to the rare endpoint, 45.141.87[.]195, over destination port 8000 using HTTP as the application-layer protocol. Within this connection, Darktrace observed the presence of a PowerShell script in the URI, specifically ‘/infect.ps1’.

    Darktrace’s analysis of this endpoint (45.141.87[.]195[:]8000/infect.ps1) and the payload it downloaded indicated it was a dropper used to deliver an obfuscated AutoIt loader. This attribution was further supported by open-source intelligence (OSINT) reporting [5]. The loader likely then injected NBMiner into a legitimate process on the customer’s environment – the first documented case of NBMiner being dropped in this way.

    Darktrace’s detection of a device making an HTTP connection with new PowerShell user agent, indicating PowerShell abuse for command-and-control (C2) communications.
    Figure 1: Darktrace’s detection of a device making an HTTP connection with new PowerShell user agent, indicating PowerShell abuse for command-and-control (C2) communications.

    Script files are often used by malicious actors for malware distribution. In cryptojacking attacks specifically, scripts are used to download and install cryptomining software, which then attempts to connect to cryptomining pools to begin mining operations [6].

    Inside the payload: Technical analysis of the malicious script and cryptomining loader

    To confidently establish that the malicious script file dropped an AutoIt loader used to deliver the NBMiner cryptominer, Darktrace’s threat researchers reverse engineered the payload. Analysis of the file ‘infect.ps1’ revealed further insights, ultimately linking it to the execution of a cryptominer loader.

    Screenshot of the ‘infect.ps1’ PowerShell script observed in the attack.
    Figure 2: Screenshot of the ‘infect.ps1’ PowerShell script observed in the attack.

    The ‘infect.ps1’ script is a heavily obfuscated PowerShell script that contains multiple variables of Base64 and XOR encoded data. The first data blob is XOR’d with a value of 97, after decoding, the data is a binary and stored in APPDATA/local/knzbsrgw.exe. The binary is AutoIT.exe, the legitimate executable of the AutoIt programming language. The script also performs a check for the existence of the registry key HKCU:\\Software\LordNet.

    The second data blob ($cylcejlrqbgejqryxpck) is written to APPDATA\rauuq, where it will later be read and XOR decoded. The third data blob ($tlswqbblxmmr)decodes to an obfuscated AutoIt script, which is written to %LOCALAPPDATA%\qmsxehehhnnwioojlyegmdssiswak. To ensure persistence, a shortcut file named xxyntxsmitwgruxuwqzypomkhxhml.lnk is created to run at startup.

     Screenshot of second stage AutoIt script.
    Figure 3: Screenshot of second stage AutoIt script.

    The observed AutoIt script is a process injection loader. It reads an encrypted binary from /rauuq in APPDATA, then XOR-decodes every byte with the key 47 to reconstruct the payload in memory. Next, it silently launches the legitimate Windows app ‘charmap.exe’ (Character Map) and obtains a handle with full access. It allocates executable and writable memory inside that process, writes the decrypted payload into the allocated region, and starts a new thread at that address. Finally, it closes the thread and process handles.

    The binary that is injected into charmap.exe is 64-bit Windows binary. On launch, it takes a snapshot of running processes and specifically checks whether Task Manager is open. If Task Manager is detected, the binary kills sigverif.exe; otherwise, it proceeds. Once the condition is met, NBMiner is retrieved from a Chimera URL (https://api[.]chimera-hosting[.]zip/frfnhis/zdpaGgLMav/nbminer[.]exe) and establishes persistence, ensuring that the process automatically restarts if terminated. When mining begins, it spawns a process with the arguments ‘-a kawpow -o asia.ravenminer.com:3838 -u R9KVhfjiqSuSVcpYw5G8VDayPkjSipbiMb.worker -i 60’ and hides the process window to evade detection.

    Observed NBMiner arguments.
    Figure 4: Observed NBMiner arguments.

    The program includes several evasion measures. It performs anti-sandboxing by sleeping to delay analysis and terminates sigverif.exe (File Signature Verification). It checks for installed antivirus products and continues only when Windows Defender is the sole protection. It also verifies whether the current user has administrative rights. If not, it attempts a User Account Control (UAC) bypass via Fodhelper to silently elevate and execute its payload without prompting the user. The binary creates a folder under %APPDATA%, drops rtworkq.dll extracted from its own embedded data, and copies ‘mfpmp.exe’ from System32 into that directory to side-load ‘rtworkq.dll’. It also looks for the registry key HKCU\Software\kap, creating it if it does not exist, and reads or sets a registry value it expects there.

    Zooming Out: Darktrace Coverage of NBMiner

    Darktrace’s analysis of the malicious PowerShell script provides clear evidence that the payload downloaded and executed the NBMiner cryptominer. Once executed, the infected device is expected to attempt connections to cryptomining endpoints (mining pools). Darktrace initially observed this on the targeted device once it started making DNS requests for a cryptominer endpoint, “gulf[.]moneroocean[.]stream” [7], one minute after the connection involving the malicious script.

    Darktrace Advanced Search logs showcasing the affected device making a DNS request for a Monero mining endpoint.
    Figure 5: Darktrace Advanced Search logs showcasing the affected device making a DNS request for a Monero mining endpoint.

    Though DNS requests do not necessarily mean the device connected to a cryptominer-associated endpoint, Darktrace detected connections to the endpoint specified in the DNS Answer field: monerooceans[.]stream, 152.53.121[.]6. The attempted connections to this endpoint over port 10001 triggered several high-fidelity model alerts in Darktrace related to possible cryptomining mining activity. The IP address and destination port combination (152.53.121[.]6:10001) has also been linked to cryptomining activity by several OSINT security vendors [8][9].

    Darktrace’s detection of a device establishing connections with the Monero Mining-associated endpoint, monerooceans[.]stream over port 10001.
    Figure 6: Darktrace’s detection of a device establishing connections with the Monero Mining-associated endpoint, monerooceans[.]stream over port 10001.

    Darktrace / NETWORK grouped together the observed indicators of compromise (IoCs) on the targeted device and triggered an additional Enhanced Monitoring model designed to identify activity indicative of the early stages of an attack. These high-fidelity models are continuously monitored and triaged by Darktrace’s SOC team as part of the Managed Threat Detection service, ensuring that subscribed customers are promptly notified of malicious activity as soon as it emerges.

    Figure 7: Darktrace’s correlation of the initial PowerShell-related activity with the cryptomining endpoint, showcasing a pattern indicative of an initial attack chain.

    Darktrace’s Cyber AI Analyst launched an autonomous investigation into the ongoing activity and was able to link the individual events of the attack, encompassing the initial connections involving the PowerShell script to the ultimate connections to the cryptomining endpoint, likely representing cryptomining activity. Rather than viewing these seemingly separate events in isolation, Cyber AI Analyst was able to see the bigger picture, providing comprehensive visibility over the attack.

    Darktrace’s Cyber AI Analyst view illustrating the extent of the cryptojacking attack mapped against the Cyber Kill Chain.
    Figure 8: Darktrace’s Cyber AI Analyst view illustrating the extent of the cryptojacking attack mapped against the Cyber Kill Chain.

    Darktrace’s Autonomous Response

    Fortunately, as this customer had Darktrace configured in Autonomous Response mode, Darktrace was able to take immediate action by preventing  the device from making outbound connections and blocking specific connections to suspicious endpoints, thereby containing the attack.

    Darktrace’s Autonomous Response actions automatically triggered based on the anomalous connections observed to suspicious endpoints.
    Figure 9: Darktrace’s Autonomous Response actions automatically triggered based on the anomalous connections observed to suspicious endpoints.

    Specifically, these Autonomous Response actions prevented the outgoing communication within seconds of the device attempting to connect to the rare endpoints.

    Figure 10: Darktrace’s Autonomous Response blocked connections to the mining-related endpoint within a second of the initial connection.

    Additionally, the Darktrace SOC team was able to validate the effectiveness of the Autonomous Response actions by analyzing connections to 152.53.121[.]6 using the Advanced Search feature. Across more than 130 connection attempts, Darktrace’s SOC confirmed that all were aborted, meaning no connections were successfully established.

    Figure 11: Advanced Search logs showing all attempted connections that were successfully prevented by Darktrace’s Autonomous Response capability.

    Conclusion

    Cryptojacking attacks will remain prevalent, as threat actors can scale their attacks to infect multiple devices and networks. What’s more, cryptomining incidents can often be difficult to detect and are even overlooked as low-severity compliance events, potentially leading to data privacy issues and significant energy bills caused by misused processing power.

    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 can detect subtle deviations that may signal a compromise.

    In this case, the cryptojacking attack was quickly identified and mitigated during the early stages of malware and cryptomining activity. Darktrace's Autonomous Response was able to swiftly contain the threat before it could advance further along the attack lifecycle, minimizing disruption and preventing the attack from potentially escalating into a more severe compromise.

    Credit to Keanna Grelicha (Cyber Analyst) and Tara Gould (Threat Research Lead)

    Appendices

    Darktrace Model Detections

    NETWORK Models:

    ·      Compromise / High Priority Crypto Currency Mining (Enhanced Monitoring Model)

    ·      Device / Initial Attack Chain Activity (Enhanced Monitoring Model)

    ·      Compromise / Suspicious HTTP and Anomalous Activity (Enhanced Monitoring Model)

    ·      Compromise / Monero Mining

    ·      Anomalous File / Script from Rare External Location

    ·      Device / New PowerShell User Agent

    ·      Anomalous Connection / New User Agent to IP Without Hostname

    ·      Anomalous Connection / Powershell to Rare External

    ·      Device / Suspicious Domain

    Cyber AI Analyst Incident Events:

    ·      Detect \ Event \ Possible HTTP Command and Control

    ·      Detect \ Event \ Cryptocurrency Mining Activity

    Autonomous Response Models:

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

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

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

    ·      Antigena / Network::External Threat::Antigena Crypto Currency Mining Block

    ·      Antigena / Network::External Threat::Antigena File then New Outbound Block

    ·      Antigena / Network::External Threat::Antigena Suspicious File Block

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

    List of Indicators of Compromise (IoCs)

    (IoC - Type - Description + Confidence)

    ·      45.141.87[.]195:8000/infect.ps1 - IP Address, Destination Port, Script - Malicious PowerShell script

    ·      gulf.moneroocean[.]stream - Hostname - Monero Endpoint

    ·      monerooceans[.]stream - Hostname - Monero Endpoint

    ·      152.53.121[.]6:10001 - IP Address, Destination Port - Monero Endpoint

    ·      152.53.121[.]6 - IP Address – Monero Endpoint

    ·      https://api[.]chimera-hosting[.]zip/frfnhis/zdpaGgLMav/nbminer[.]exe – Hostname, Executable File – NBMiner

    ·      Db3534826b4f4dfd9f4a0de78e225ebb – Hash – NBMiner loader

    MITRE ATT&CK Mapping

    (Tactic – Technique – Sub-Technique)

    ·      Vulnerabilities – RESOURCE DEVELOPMENT – T1588.006 - T1588

    ·      Exploits – RESOURCE DEVELOPMENT – T1588.005 - T1588

    ·      Malware – RESOURCE DEVELOPMENT – T1588.001 - T1588

    ·      Drive-by Compromise – INITIAL ACCESS – T1189

    ·      PowerShell – EXECUTION – T1059.001 - T1059

    ·      Exploitation of Remote Services – LATERAL MOVEMENT – T1210

    ·      Web Protocols – COMMAND AND CONTROL – T1071.001 - T1071

    ·      Application Layer Protocol – COMMAND AND CONTROL – T1071

    ·      Resource Hijacking – IMPACT – T1496

    ·      Obfuscated Files - DEFENSE EVASION - T1027                

    ·      Bypass UAC - PRIVILEGE ESCALATION – T1548.002

    ·      Process Injection – PRIVILEGE ESCALATION – T055

    ·      Debugger Evasion – DISCOVERY – T1622

    ·      Logon Autostart Execution – PERSISTENCE – T1547.009

    References

    [1] https://www.darktrace.com/cyber-ai-glossary/cryptojacking#:~:text=Battery%20drain%20and%20overheating,fee%20to%20%E2%80%9Cmine%20cryptocurrency%E2%80%9D.

    [2] https://coinmarketcap.com/

    [3] https://www.ibm.com/think/topics/cryptojacking

    [4] https://thehackernews.com/2025/07/3500-websites-hijacked-to-secretly-mine.html

    [5] https://urlhaus.abuse.ch/url/3589032/

    [6] https://www.logpoint.com/en/blog/uncovering-illegitimate-crypto-mining-activity/

    [7] https://www.virustotal.com/gui/domain/gulf.moneroocean.stream/detection

    [8] https://www.virustotal.com/gui/domain/monerooceans.stream/detection

    [9] https://any.run/report/5aa8cd5f8e099bbb15bc63be52a3983b7dd57bb92566feb1a266a65ab5da34dd/351eca83-ef32-4037-a02f-ac85a165d74e

    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 without notice.

    Continue reading
    About the author
    Keanna Grelicha
    Cyber Analyst

    Blog

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    Identity

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    August 29, 2025

    From VPS to Phishing: How Darktrace Uncovered SaaS Hijacks through Virtual Infrastructure Abuse

    VPS phishingDefault blog imageDefault blog image

    What is a VPS and how are they abused?

    A Virtual Private Server (VPS) is a virtualized server that provides dedicated resources and control to users on a shared physical device.  VPS providers, long used by developers and businesses, are increasingly misused by threat actors to launch stealthy, scalable attacks. While not a novel tactic, VPS abuse is has seen an increase in Software-as-a-Service (SaaS)-targeted campaigns as it enables attackers to bypass geolocation-based defenses by mimicking local traffic, evade IP reputation checks with clean, newly provisioned infrastructure, and blend into legitimate behavior [3].

    VPS providers like Hyonix and Host Universal offer rapid setup and minimal open-source intelligence (OSINT) footprint, making detection difficult [1][2]. These services are not only fast to deploy but also affordable, making them attractive to attackers seeking anonymous, low-cost infrastructure for scalable campaigns. Such attacks tend to be targeted and persistent, often timed to coincide with legitimate user activity, a tactic that renders traditional security tools largely ineffective.

    Darktrace’s investigation into Hyonix VPS abuse

    In May 2025, Darktrace’s Threat Research team investigated a series of incidents across its customer base involving VPS-associated infrastructure. The investigation began with a fleet-wide review of alerts linked to Hyonix (ASN AS931), revealing a noticeable spike in anomalous behavior from this ASN in March 2025. The alerts included brute-force attempts, anomalous logins, and phishing campaign-related inbox rule creation.

    Darktrace identified suspicious activity across multiple customer environments around this time, but two networks stood out. In one instance, two internal devices exhibited mirrored patterns of compromise, including logins from rare endpoints, manipulation of inbox rules, and the deletion of emails likely used in phishing attacks. Darktrace traced the activity back to IP addresses associated with Hyonix, suggesting a deliberate use of VPS infrastructure to facilitate the attack.

    On the second customer network, the attack was marked by coordinated logins from rare IPs linked to multiple VPS providers, including Hyonix. This was followed by the creation of inbox rules with obfuscated names and attempts to modify account recovery settings, indicating a broader campaign that leveraged shared infrastructure and techniques.

    Darktrace’s Autonomous Response capability was not enabled in either customer environment during these attacks. As a result, no automated containment actions were triggered, allowing the attack to escalate without interruption. Had Autonomous Response been active, Darktrace would have automatically blocked connections from the unusual VPS endpoints upon detection, effectively halting the compromise in its early stages.

    Case 1

    Timeline of activity for Case 1 - Unusual VPS logins and deletion of phishing emails.
    Figure 1: Timeline of activity for Case 1 - Unusual VPS logins and deletion of phishing emails.

    Initial Intrusion

    On May 19, 2025, Darktrace observed two internal devices on one customer environment initiating logins from rare external IPs associated with VPS providers, namely Hyonix and Host Universal (via Proton VPN). Darktrace recognized that these logins had occurred within minutes of legitimate user activity from distant geolocations, indicating improbable travel and reinforcing the likelihood of session hijacking. This triggered Darktrace / IDENTITY model “Login From Rare Endpoint While User Is Active”, which highlights potential credential misuse when simultaneous logins occur from both familiar and rare sources.  

    Shortly after these logins, Darktrace observed the threat actor deleting emails referring to invoice documents from the user’s “Sent Items” folder, suggesting an attempt to hide phishing emails that had been sent from the now-compromised account. Though not directly observed, initial access in this case was likely achieved through a similar phishing or account hijacking method.

     Darktrace / IDENTITY model "Login From Rare Endpoint While User Is Active", which detects simultaneous logins from both a common and a rare source to highlight potential credential misuse.
    Figure 2: Darktrace / IDENTITY model "Login From Rare Endpoint While User Is Active", which detects simultaneous logins from both a common and a rare source to highlight potential credential misuse.

    Case 2

    Timeline of activity for Case 2 – Coordinated inbox rule creation and outbound phishing campaign.
    Figure 3: Timeline of activity for Case 2 – Coordinated inbox rule creation and outbound phishing campaign.

    In the second customer environment, Darktrace observed similar login activity originating from Hyonix, as well as other VPS providers like Mevspace and Hivelocity. Multiple users logged in from rare endpoints, with Multi-Factor Authentication (MFA) satisfied via token claims, further indicating session hijacking.

    Establishing control and maintaining persistence

    Following the initial access, Darktrace observed a series of suspicious SaaS activities, including the creation of new email rules. These rules were given minimal or obfuscated names, a tactic often used by attackers to avoid drawing attention during casual mailbox reviews by the SaaS account owner or automated audits. By keeping rule names vague or generic, attackers reduce the likelihood of detection while quietly redirecting or deleting incoming emails to maintain access and conceal their activity.

    One of the newly created inbox rules targeted emails with subject lines referencing a document shared by a VIP at the customer’s organization. These emails would be automatically deleted, suggesting an attempt to conceal malicious mailbox activity from legitimate users.

    Mirrored activity across environments

    While no direct lateral movement was observed, mirrored activity across multiple user devices suggested a coordinated campaign. Notably, three users had near identical similar inbox rules created, while another user had a different rule related to fake invoices, reinforcing the likelihood of a shared infrastructure and technique set.

    Privilege escalation and broader impact

    On one account, Darktrace observed “User registered security info” activity was shortly after anomalous logins, indicating attempts to modify account recovery settings. On another, the user reset passwords or updated security information from rare external IPs. In both cases, the attacker’s actions—including creating inbox rules, deleting emails, and maintaining login persistence—suggested an intent to remain undetected while potentially setting the stage for data exfiltration or spam distribution.

    On a separate account, outbound spam was observed, featuring generic finance-related subject lines such as 'INV#. EMITTANCE-1'. At the network level, Darktrace / NETWORK detected DNS requests from a device to a suspicious domain, which began prior the observed email compromise. The domain showed signs of domain fluxing, a tactic involving frequent changes in IP resolution, commonly used by threat actors to maintain resilient infrastructure and evade static blocklists. Around the same time, Darktrace detected another device writing a file named 'SplashtopStreamer.exe', associated with the remote access tool Splashtop, to a domain controller. While typically used in IT support scenarios, its presence here may suggest that the attacker leveraged it to establish persistent remote access or facilitate lateral movement within the customer’s network.

    Conclusion

    This investigation highlights the growing abuse of VPS infrastructure in SaaS compromise campaigns. Threat actors are increasingly leveraging these affordable and anonymous hosting services to hijack accounts, launch phishing attacks, and manipulate mailbox configurations, often bypassing traditional security controls.

    Despite the stealthy nature of this campaign, Darktrace detected the malicious activity early in the kill chain through its Self-Learning AI. By continuously learning what is normal for each user and device, Darktrace surfaced subtle anomalies, such as rare login sources, inbox rule manipulation, and concurrent session activity, that likely evade traditional static, rule-based systems.

    As attackers continue to exploit trusted infrastructure and mimic legitimate user behavior, organizations should adopt behavioral-based detection and response strategies. Proactively monitoring for indicators such as improbable travel, unusual login sources, and mailbox rule changes, and responding swiftly with autonomous actions, is critical to staying ahead of evolving threats.

    Credit to Rajendra Rushanth (Cyber Analyst), Jen Beckett (Cyber Analyst) and Ryan Traill (Analyst Content Lead)

    References

    ·      1: https://cybersecuritynews.com/threat-actors-leveraging-vps-hosting-providers/

    ·      2: https://threatfox.abuse.ch/asn/931/

    ·      3: https://www.cyfirma.com/research/vps-exploitation-by-threat-actors/

    Appendices

    Darktrace Model Detections

    •   SaaS / Compromise / Unusual Login, Sent Mail, Deleted Sent

    •   SaaS / Compromise / Suspicious Login and Mass Email Deletes

    •   SaaS / Resource / Mass Email Deletes from Rare Location

    •   SaaS / Compromise / Unusual Login and New Email Rule

    •   SaaS / Compliance / Anomalous New Email Rule

    •   SaaS / Resource / Possible Email Spam Activity

    •   SaaS / Unusual Activity / Multiple Unusual SaaS Activities

    •   SaaS / Unusual Activity / Multiple Unusual External Sources For SaaS Credential

    •   SaaS / Access / Unusual External Source for SaaS Credential Use

    •   SaaS / Compromise / High Priority Login From Rare Endpoint

    •   SaaS / Compromise / Login From Rare Endpoint While User Is Active

    List of Indicators of Compromise (IoCs)

    Format: IoC – Type – Description

    •   38.240.42[.]160 – IP – Associated with Hyonix ASN (AS931)

    •   103.75.11[.]134 – IP – Associated with Host Universal / Proton VPN

    •   162.241.121[.]156 – IP – Rare IP associated with phishing

    •   194.49.68[.]244 – IP – Associated with Hyonix ASN

    •   193.32.248[.]242 – IP – Used in suspicious login activity / Mullvad VPN

    •   50.229.155[.]2 – IP – Rare login IP / AS 7922 ( COMCAST-7922 )

    •   104.168.194[.]248 – IP – Rare login IP / AS 54290 ( HOSTWINDS )

    •   38.255.57[.]212 – IP – Hyonix IP used during MFA activity

    •   103.131.131[.]44 – IP – Hyonix IP used in login and MFA activity

    •   178.173.244[.]27 – IP – Hyonix IP

    •   91.223.3[.]147 – IP – Mevspace Poland, used in multiple logins

    •   2a02:748:4000:18:0:1:170b[:]2524 – IPv6 – Hivelocity VPS, used in multiple logins and MFA activity

    •   51.36.233[.]224 – IP – Saudi ASN, used in suspicious login

    •   103.211.53[.]84 – IP – Excitel Broadband India, used in security info update

    MITRE ATT&CK Mapping

    Tactic – Technique – Sub-Technique

    •   Initial Access – T1566 – Phishing

                           T1566.001 – Spearphishing Attachment

    •   Execution – T1078 – Valid Accounts

    •   Persistence – T1098 – Account Manipulation

                           T1098.002 – Exchange Email Rules

    •   Command and Control – T1071 – Application Layer Protocol

                           T1071.001 – Web Protocols

    •   Defense Evasion – T1036 – Masquerading

    •   Defense Evasion – T1562 – Impair Defenses

                           T1562.001 – Disable or Modify Tools

    •   Credential Access – T1556 – Modify Authentication Process

                           T1556.004 – MFA Bypass

    •   Discovery – T1087 – Account Discovery

    •      Impact – T1531 – Account Access Removal

    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 without notice.

    Continue reading
    About the author
    Rajendra Rushanth
    Cyber Analyst
    Your data. Our AI.
    Elevate your network security with Darktrace AI