IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.
« File Deletion via Shred File made Immutable by Chattr »
Elastic Docs ›Elastic Security Solution [8.5] ›Detections and alerts ›Prebuilt rule reference

File Permission Modification in Writable Directory

edit

File Permission Modification in Writable Directory

edit

Identifies file permission modifications in common writable directories by a non-root user. Adversaries often drop files or payloads into a writable directory and change permissions prior to execution.

Rule type: query

Rule indices:

  • auditbeat-*
  • logs-endpoint.events.*

Severity: low

Risk score: 21

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Host
  • Linux
  • Threat Detection
  • Defense Evasion

Version: 100 (version history)

Added (Elastic Stack release): 7.8.0

Last modified (Elastic Stack release): 8.5.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positives

edit

Certain programs or applications may modify files or change ownership in writable directories. These can be exempted by username.

Rule query

edit
event.category:process and event.type:(start or process_started) and
process.name:(chmod or chown or chattr or chgrp) and
process.working_directory:(/tmp or /var/tmp or /dev/shm) and not
user.name:root

Threat mapping

edit

Framework: MITRE ATT&CKTM

Rule version history

edit
Version 100 (8.5.0 release)
  • Formatting only
Version 7 (8.4.0 release)
  • Formatting only
Version 6 (7.12.0 release)
  • Formatting only
Version 5 (7.11.2 release)
  • Formatting only
Version 4 (7.10.0 release)
  • Formatting only
Version 3 (7.9.1 release)
  • Formatting only
Version 2 (7.9.0 release)

  • Updated query, changed from:

    event.action:executed and process.name:(chmod or chown or chattr or
chgrp) and process.working_directory:(/tmp or /var/tmp or /dev/shm)
and not user.name:root
« File Deletion via Shred File made Immutable by Chattr »