Malicious Arkanix Stealer C2 Communication via Custom User-Agent

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects outbound HTTP traffic carrying the hardcoded User-Agent string used by the Arkanix C++ and Python infostealer. Kaspersky observed Arkanix identifying itself to its panel with the ArkanixStealer client string while requesting stealer and hidden VNC modules. This distinctive agent is a reliable indicator of an infected host communicating with the stealer backend to receive payloads and exfiltrate credentials.

Reporting behind it

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Malicious Arkanix Stealer C2 Communication via Custom User-Agent

Pivot detection · T1071.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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