Suspicious Text-File Payload Staging in Temp (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 specifically named text staging files used to hold base64-encoded .NET loaders and encrypted configuration. The SHADOW#REACTOR campaign used a text-only staging pipeline before in-memory Remcos RAT deployment.

Reporting behind it

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Suspicious Text-File Payload Staging in Temp (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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