huntrule

Windows RunOnce Execution via runonce.exe With AlternateShellStartup and /r

Alerts on runonce.exe executing with /AlternateShellStartup and /r, consistent with configured RunOnce persistence behavior.

FreeReviewedSigma · Low · v1
Product
windows
Category
process_creation
Author
Avneet Singh @v3t0_, oscd.community, Christopher Peacock @SecurePeacock (updated) (SigmaHQ), DRL 1.1
Published
2020-10-18
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Persistence → 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 flags process creation of runonce.exe when it is invoked as the “Run Once Wrapper” with command-line parameters that include /AlternateShellStartup and /r. Such behavior matters because it can trigger attacker-controlled or persistence-oriented commands to run once during the system’s startup sequence or at a scheduled time. The detection relies on Windows process creation telemetry, matching the process image path, process description, and specific command-line argument patterns.

Reporting behind it

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Malicious WDigest UseLogonCredential Enabled for Cleartext Credential Theft (via registry_set)
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Windows RunOnce Execution via runonce.exe With AlternateShellStartup and /r
Pivot detection · T1112 · 9 related

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