Suspicious Cobalt Strike DNS Beacon Default Subdomain Query Linked to Cozy Bear

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.004DNS
Exfiltration
Impact

What it detects

This rule detects DNS queries whose labels match Cobalt Strike DNS Beacon default staging and callback prefixes such as post.1, aaa.stage, and baa.stage, a command-and-control pattern tied to Cozy Bear operations. These default beacon subdomains are distinctive constants left in unmodified Cobalt Strike profiles, so queries containing them are a strong indicator of DNS-based C2.

Reporting behind it

Related detections9 linkedT1071.004 — drag to rearrange

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Malicious PIPEDANCE Named Pipe Command and Control Channel via Pipe Created

Suspicious DNS Query for Tor Onion Domain

Possible DNS Tunneling via Excessively Long Query Name

Suspicious Cobalt Strike DNS Beacon Default Subdomain Query Linked to Cozy Bear

Pivot detection · T1071.004 · 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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