Suspicious JSP Webshell Written to SAP irj work Directory (via file_event)

PremiumReviewedSigma · High · v1
Category
file_event
Author
HuntRule
Published
2026-05-15
Updated
2026-08-28

ATT&CK techniques

Persistence
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects JSP files being written under the SAP servlet_jsp irj work directory, the deployment location where CVE-2025-31324 exploitation dropped webshells such as forwardsap.jsp and helper.jsp. New JSP files appearing in this runtime path indicate server software component abuse. This is a reliable webshell persistence signal.

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Suspicious JSP Webshell Written to SAP irj work Directory (via file_event)
Pivot detection · T1505.003 · 9 related

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