Malicious MetaStealer C2 via cpp-httplib User-Agent (via proxy)

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 web requests presenting the cpp-httplib user-agent to the MetaStealer tasking endpoints such as api/client/new and tasks/get_worker. The combination of the library user-agent and these fixed URIs is a specific C2 fingerprint. Matching it surfaces hosts beaconing to MetaStealer infrastructure to register and receive stealer tasks.

Reporting behind it

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Malicious MetaStealer C2 via cpp-httplib User-Agent (via proxy)

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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