IMPORTANT: No additional bug fixes or documentation updates will be released for this version. For the latest information, see the current release documentation.
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Elastic Docs ›Elastic Security Solution [8.3] ›Detections and alerts ›Prebuilt rule reference

Unusual Process Execution - Temp

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Unusual Process Execution - Temp

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Identifies processes running in a temporary folder. This is sometimes done by adversaries to hide malware.

Rule type: query

Rule indices:

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

Severity: medium

Risk score: 47

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

Version: 8 (version history)

Added (Elastic Stack release): 7.6.0

Last modified (Elastic Stack release): 8.3.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positives

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Build systems, like Jenkins, may start processes in the /tmp directory. These can be exempted by name or by username.

Rule query

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event.category:process and event.type:(start or process_started) and
process.working_directory:/tmp and not process.parent.name:(update-
motd-updates-available or apt or apt-* or
cnf-update-db or appstreamcli or
unattended-upgrade or packagekitd) and
not process.args:(/usr/lib/update-notifier/update-motd-updates-
available or /var/lib/command-not-found/)

Rule version history

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Version 8 (8.3.0 release)

  • Updated query, changed from:

    event.category:process and event.type:(start or process_started) and
process.working_directory:/tmp
Version 7 (7.12.0 release)
  • Formatting only
Version 6 (7.11.2 release)
  • Formatting only
Version 5 (7.10.0 release)
  • Formatting only
Version 4 (7.9.1 release)
  • Formatting only
Version 3 (7.9.0 release)

  • Updated query, changed from:

    process.working_directory:/tmp and event.action:executed
Version 2 (7.7.0 release)

  • Updated query, changed from:

    process.working_directory: /tmp and event.action:executed
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