Suspicious Base64 Decode Piped to Python Interpreter for In-Memory Execution (via process_creation)

ATT&CK techniques

Defense Evasion

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

What it detects

This rule detects a shell command that decodes Base64 content and pipes it directly into a Python interpreter, often alongside an LD_LIBRARY_PATH override. During Ivanti Connect Secure exploitation the actor executed obfuscated Python payloads this way to run tooling without touching disk. Chaining base64 decoding into python is a common obfuscated in-memory execution pattern on Linux appliances.

Reporting behind it

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Suspicious Base64 Decode Piped to Python Interpreter for In-Memory Execution (via process_creation)

Pivot detection · T1027 · 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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