Suspicious C2 Beacon via cpp-httplib 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 requests carrying the cpp-httplib user agent, matching the Potemkin loader command-and-control channel observed with the test_agent identifier. The loader is built on the cpp-httplib library and this user agent rarely appears in legitimate enterprise browsing. Its presence in proxy or web telemetry indicates loader check-in and tasking.

Reporting behind it

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Suspicious C2 Beacon via cpp-httplib 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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