Malicious Rundll32 Loading Update DLL from AppData Custom_update with scab Export

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-21
Updated
2026-09-21

ATT&CK techniques

Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule detects rundll32.exe loading an Update DLL from a user AppData Custom_update directory and calling the scab export, the loader execution used by DanaBot to run IcedID. This proxy execution runs the malicious module under a trusted signed binary to evade application controls.

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Malicious Rundll32 Loading Update DLL from AppData Custom_update with scab Export
Pivot detection · T1218.011 · 9 related

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