Suspicious MSHTA Execution of Polyglot PDF File Spawned by cmd (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-07-19
Updated
2026-08-28

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 detects mshta.exe launched by cmd.exe with a PDF file argument, matching the UNK_CraftyCamel chain where an LNK ran cmd then mshta to execute a PDF and HTA polyglot. Legitimate mshta rarely processes files with a .pdf extension.

Related detections9 linkedT1218.005 — drag to rearrange
Suspicious PowerShell Spawned by mshta.exe in FakeSG Chain (via process_creation)
Suspicious Hidden PowerShell Spawned by MSHTA for Boot Persistence (via process_creation)
Malicious HTA Payload Download and Execution via PowerShell One-Liner (via process_creation)
Suspicious RunMRU Entry Launching LOLBIN via ClickFix Run Dialog
Suspicious mshta Executing Remote Content via ClickFix Lure
Suspicious mshta Launched from Explorer via ClickFix Run Dialog (via process_creation)
Suspicious msdt Execution of Audio Diagnostic via UNC1069 ClickFix
Suspicious PowerShell Loader Spawned by mshta via UNC5142 ClickFix
Suspicious Script Interpreter Spawned by mshta
Suspicious MSHTA Execution of Polyglot PDF File Spawned by cmd (via process_creation)
Pivot detection · T1218.005 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.