Windows Process Creation: Command Line Obfuscation via Escape Characters

Identifies Windows process command lines containing escape-character URL obfuscation patterns.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
juju4 (SigmaHQ), DRL 1.1
Published
2018-12-11
Updated
2026-07-30

ATT&CK techniques

Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule flags Windows process creation events where the command line contains specific escape-character patterns often used to obfuscate URLs. Attackers may use these sequences to evade string-based detections and make command intent harder to read. It relies on process creation telemetry including the process CommandLine field matching the defined obfuscated substrings.

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Windows Process Creation: Command Line Obfuscation via Escape Characters
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.