huntrule

Windows process creation matching EmpireMonkey-style jscript execution from Temp Errors.bat

Alerts on Windows executions that combine /e:jscript with a \Local\Temp\Errors.bat batch path.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
Markus Neis, Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2019-04-02
Updated
2026-07-31
AnalysisDetection

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 flags Windows process creation events whose command line contains both an inline jscript execution switch and a reference to a temporary Errors.bat file. Attackers may use script-based execution from writable temp locations to run malicious payloads with fewer visible artifacts. The detection relies on process creation telemetry with full command-line data that includes both of these substrings.

Reporting behind it

Related detections9 linkedT1218.010 — drag to rearrange
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Suspicious Regsvr32 Execution of SafePay Loader DLL
Suspicious Scheduled Task Running Regsvr32 with Extreme Duration by StaryDobry
Malicious DynamicWrapperX Registration via regsvr32 (via process_creation)
Suspicious Run Key Persistence Executing regsvr32
Suspicious regsvr32 Registering DLL from User AppData
Malicious Regsvr32 Loading Masqueraded VPN DLL via Process Creation
Malicious Regsvr32 ShellExec_RunDLL Proxy Execution (via process_creation)
Suspicious DLL Execution via Regsvr32 DllInstall of dat File
Windows process creation matching EmpireMonkey-style jscript execution from Temp Errors.bat
Pivot detection · T1218.010 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. v1
    No changelog recorded for this version.2026-07-30

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