Malicious SSLoad Downloader C2 Beacon via Custom SSLoad 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 HTTP traffic carrying the hardcoded SSLoad User-Agent used by the SSLoad downloader when it registers a fingerprinted host and beacons for tasks to its command-and-control server. This bespoke agent string is not produced by legitimate software and identifies the downloader stage of the intrusion on the wire.

Reporting behind it

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Malicious SSLoad Downloader C2 Beacon via Custom SSLoad 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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