Suspicious Persistence via Shell Script Dropped in profile.d Directory (via file_event)

PremiumReviewedSigma · Medium · v1
Product
linux
Category
file_event
Author
HuntRule
Published
2026-06-01
Updated
2026-08-28

ATT&CK techniques

Persistence → Priv Esc
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Defense Evasion

  6. Cred Access

  7. Discovery

  8. Lateral Movement

  9. Collection

  10. C2

  11. Exfiltration

  12. Impact

What it detects

This rule detects creation of a shell script under /etc/profile.d/ that executes for every interactive login shell. During Ivanti post-exploitation lateral movement the actor planted a cron.sh style script in profile.d to re-establish access on login. New executable scripts in profile.d are a well-known Linux persistence mechanism warranting review.

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Suspicious Persistence via Shell Script Dropped in profile.d Directory (via file_event)
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.