Suspicious Fake GIF Magic Header Written to Disguise Payload File (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 printf being used to write a GIF magic-byte header into a .gif file as a masquerading step. During Ivanti post-exploitation the actor prepended fake GIF headers so malicious content would pass as harmless image files. Manufacturing image magic bytes over shell is a deliberate file-type masquerading and obfuscation behavior.

Reporting behind it

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Suspicious Fake GIF Magic Header Written to Disguise Payload File (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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