UDPGangster Campaigns Target Multiple Countries

UDPGangster Campaigns Target Multiple Countries

UDPGangster is a UDP-based backdoor attributed to the MuddyWater group that is distributed via macro-enabled Microsoft Word documents to gain initial access and establish C2 over UDP. The malware uses extensive anti-analysis checks, persistence via registry startup, and capabilities for remote command execution and file exfiltration to target users in Turkey, Israel, and Azerbaijan. #UDPGangster #MuddyWater

Keypoints

  • UDPGangster is delivered via malicious Word documents with embedded VBA macros that prompt users to “Enable Content” to execute the payload.
  • The backdoor communicates with its C2 over UDP (observed C2: 157.20.182.75:1269) and supports remote command execution, file extraction, and payload deployment.
  • Samples include robust anti-analysis and sandbox/VM detection routines (debugger checks, CPU/RAM checks, virtual NIC MAC prefixes, WMI and registry scans, and sandbox DLL/process checks).
  • Persistence is achieved by copying the binary to %AppData%RoamingLow as SystemProc.exe and writing a Startup value under HKCUSOFTWAREMicrosoftWindowsCurrentVersionExplorerUser Shell.
  • Telemetry links campaigns to recipients in Turkey, Israel, and Azerbaijan and shows shared infrastructure and PDB paths tying activity to MuddyWater.
  • Decoy content in documents (images and text) is used to distract victims while macros decode and drop the UDPGangster payload.
  • Fortinet products detect and block the threat and offer remediation and user-training recommendations to mitigate similar phishing-based intrusions.

MITRE Techniques

  • [T1566.001 ] Phishing: Spearphishing Attachment – The campaign delivers malicious Word documents as attachments. [‘includes two attachments named seminer.doc and seminer.zip.’]
  • [T1204.002 ] User Execution: Malicious File (Office Macros) – VBA macros run on Document_Open() to decode and drop payloads when users enable content. [‘Enable Content’ / ‘The macro uses the Document_Open() event to automatically execute’]
  • [T1105 ] Ingress Tool Transfer – The macro drops and executes a payload that copies itself to AppData and can deploy additional payloads. [‘copying itself to %AppData%RoamingLow as SystemProc.exe’ / ‘Triggers the execution of additional payloads’]
  • [T1547.001 ] Boot or Logon Autostart Execution: Registry Run Keys and Startup Folder – Malware writes a Startup value under a HKCU registry key to establish persistence. [‘writing the path to the Startup value under the registry key:HKCUSOFTWAREMicrosoftWindowsCurrentVersionExplorerUser Shell.’]
  • [T1059.003 ] Command and Scripting Interpreter: Windows Command Shell – The backdoor can launch remote commands via cmd.exe. [‘Launches remote command execution via cmd.exe’]
  • [T1041 ] Exfiltration Over C2 Channel – UDPGangster can extract files from victims and send collected data to a remote C2 over UDP. [‘Extracts files from the victim’ / ‘sends the data to its C2 server at 157.20.182.75 over UDP port 1269.’]
  • [T1071 ] Application Layer Protocol – C2 over UDP – The malware communicates with its command-and-control server using UDP to evade typical defenses. [‘communicates with its C2 server using the UDP protocol.’]
  • [T1082 ] System Information Discovery – The malware collects host details (computer name, domain/workgroup, OS version, username) for profiling. [‘collects system details (computer name, domain/workgroup, OS version, and username)’]
  • [T1027 ] Obfuscated Files or Information – The dropper decodes Base64-encoded content and the malware encodes data using an ROR-based transformation before exfiltration. [‘decoding Base64-encoded data from a hidden form field’ / ‘encodes them using an ROR-based transformation’]
  • [T1497 ] Virtualization/Sandbox Evasion – The sample performs many sandbox/VM and debugger checks (CPU cores, RAM size, virtual NIC MAC prefixes, WMI/registry/driver/service/process checks, sandbox DLLs). [‘performs several checks to evade analysis: 1. Debugger detection… 2. CPU environment… 4. Virtual adapter MAC prefixes… 8. Sandbox detection’]

Indicators of Compromise

  • [IP Address ] C2 and infrastructure – 157.20.182.75 (C2 server observed communicating over UDP port 1269)
  • [Domain / URL ] Malicious hosting and lure document – reminders[.]trahum[.]org, hxxps://reminders[.]trahum[.]org/Scheduled_Internet_Outages.doc
  • [File Name ] Dropper and installed binary – Scheduled_Internet_Outages.doc (decoy), seminer.doc (phishing attachment), SystemProc.exe (installed persistence filename)
  • [Mutex ] Runtime artifact – xhxhxhxhxhxpp (mutex created by UDPGangster)
  • [PDB Path ] Build artifacts linking samples – C:Usersgangstersourcereposudp_3.0…udp_3.0.pdb; C:UsersSURGEsourcereposudp_3.0…udp_3.0.pdb
  • [File Hash ] Malicious document hash – 7ea4b307e84c8b32c0220eca13155a4cf66617241f96b8af26ce2db8115e3d53 (document sample)
  • [Email ] Phishing message content/signature blob – d177cf65a17bffcd152c5397600950fc0f81f0099… (long hex-encoded message/blob observed in reporting)


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