Malicious D3f@ck Loader C2 via Java User-Agent Ready Beacon (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 D3F@ck loader command-and-control traffic identified by the hardcoded Java/1.8.0_101 user-agent combined with an event=ready status parameter in the request URI. This loader reports staged status values such as ready, downloaded and finished to its C2. The fixed Java user-agent from a non-Java host is a strong indicator of the loader beacon.

Reporting behind it

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Malicious D3f@ck Loader C2 via Java User-Agent Ready Beacon (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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