Malicious Encrypted Reverse Shell via Netcat and GPG on Linux

ATT&CK techniques

Execution → C2

Recon
Resource Dev
Initial Access
Execution
- T1059.004Unix Shell
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1071.001Web Protocols
Exfiltration
Impact

What it detects

This rule detects a command pipeline that reads from a netcat listener decrypts the traffic with gpg and pipes it into a shell which the opportunistic Log4j campaign uses to run an encrypted reverse shell that evades network content inspection.

Reporting behind it

Related detections9 linkedT1071.001 — drag to rearrange

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Suspicious UAT-10608 Credential Harvesting C2 Beacon via HTTP

Malicious BadIIS C2 Communication via lwxatisme User-Agent

Malicious Encrypted Reverse Shell via Netcat and GPG on Linux

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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