Suspicious FinCounter DNS Tunneling Query via dns_query

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 leftmost label begins with the counter prefix used by the FinCounter DNS tunneling toolkit. Unit 42 catalogued this fixed prefix as a distinctive encoding marker of FinCounter command-and-control over DNS, so repeated queries of this shape from a host suggest a covert DNS tunnel.

Reporting behind it

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Suspicious FinCounter DNS Tunneling Query via dns_query

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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