Suspicious PowerShell Payload Extraction from PNG Polyglot via findstr

ATT&CK techniques

Execution → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
- T1059.001PowerShell
Persistence
Priv Esc
Defense Evasion
- T1027.003Steganography
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects use of the findstr utility to extract an appended PowerShell payload from a PNG image and pipe it into PowerShell for execution. This polyglot steganography technique conceals script code after the PNG end marker so it can be recovered with a native search utility and run in memory.

Reporting behind it

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Suspicious PowerShell Payload Extraction from PNG Polyglot via findstr

Pivot detection · T1059.001 · 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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