Suspicious Subtitle File Parsing for Staged Command Execution

ATT&CK techniques

Execution → Defense Evasion

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

What it detects

This rule detects a command that reads a subtitle srt file and pipes selected lines through findstr and more to extract and run embedded script code. This is the first stage of a fake movie torrent that delivers Agent Tesla through a layered PowerShell chain.

Reporting behind it

Related detections9 linkedT1140 — drag to rearrange

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Obfuscated File Decoding via Certutil (via process_creation)

Suspicious Subtitle File Parsing for Staged Command Execution

Pivot detection · T1140 · 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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