Malicious Kazuar Backdoor C2 via Hardcoded HTTP Cookie by Pensive Ursa

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 Cookie value used by the upgraded Kazuar .NET backdoor attributed to Pensive Ursa (Turla). The backdoor beacons with a static cookie GUID that identifies its command and control channel which makes it a high fidelity indicator of an active Turla implant.

Reporting behind it

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Malicious Kazuar Backdoor C2 via Hardcoded HTTP Cookie by Pensive Ursa

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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