Suspicious Ivanti Dropper Hidden Files in /tmp During CVE-2025-22457 Exploitation (via file_event)

PremiumReviewedSigma · Medium · v1
Product
linux
Category
file_event
Author
HuntRule
Published
2026-06-25
Updated
2026-08-28

ATT&CK techniques

Initial Access
  1. Recon

  2. Resource Dev

  3. Execution

  4. Persistence

  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 creation of the hidden single-letter dropper files in /tmp used during CVE-2025-22457 exploitation to stage the TRAILBLAZE and BRUSHFIRE injection chain. These short hidden paths on the Ivanti appliance indicate active exploitation and payload staging.

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Suspicious Ivanti Dropper Hidden Files in /tmp During CVE-2025-22457 Exploitation (via file_event)
Pivot detection · T1190 · 9 related

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