Suspicious Base64 Decoded Payload Piped to Shell

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.004Unix Shell
Persistence
Priv Esc
Defense Evasion
- T1027Obfuscated Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects an echoed base64 blob being decoded and piped directly into an interactive shell on Linux, an obfuscated execution technique used after ActiveMQ CVE-2023-46604 exploitation. Attackers use this to hide payload contents and run commands without dropping a file. Chaining base64 decode into bash is rarely legitimate and indicates obfuscated code execution.

Reporting behind it

Related detections9 linkedT1059.004 — drag to rearrange

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Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell

Suspicious Python Interpreter Launching Encoded PowerShell via subprocess

Suspicious Base64 Decoded Payload Piped to Shell

Pivot detection · T1059.004 · 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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