Obfuscated Fickle Stealer Injection Path Store prepares.dat Under Public (via file_event)

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 creation of prepares.dat in the public users directory, the file where Fickle Stealer stores base64-encoded paths of injected components for its multi-stage execution. Adversaries leverage this world-writable location to persist loader state, making detection of the fixed filename and path a useful indicator of an active Fickle infection.

Reporting behind it

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Obfuscated Fickle Stealer Injection Path Store prepares.dat Under Public (via file_event)

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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