Malicious LSB Steganography Image Decoding via PowerShell (via ps_script)

ATT&CK techniques

Execution → Defense Evasion

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

What it detects

This rule detects PowerShell loading an image as a bitmap and iterating pixel values to extract an embedded payload. The Caminho loader used a GetPixel loop over a downloaded image to decode a hidden .NET assembly for fileless execution.

Reporting behind it

Related detections9 linkedT1059.001 — drag to rearrange

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Malicious LSB Steganography Image Decoding via PowerShell (via ps_script)

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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