Linux process discovery via grep/egrep searching for security software strings

Alerts when grep/egrep on Linux searches command lines for indicators of security/monitoring tools.

FreeReviewedSigma · Low · v2
Product
linux
Category
process_creation
Author
Daniil Yugoslavskiy, oscd.community (SigmaHQ), DRL 1.1
Published
2020-10-19
Updated
2026-07-31
title: Linux process discovery via grep/egrep searching for security software strings
id: 546b64f5-ffbd-4a9a-b891-34f78508d6dc
status: test
description: This rule flags Linux process executions where the binary name ends with /grep or /egrep and the command line contains one of several strings associated with security and telemetry software. Attackers may use simple text-search utilities to enumerate installed tools (e.g., vulnerability scanners, log shippers, monitoring/agent processes) during discovery. It relies on process creation telemetry that includes the executable path and full command line.
references:
  - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1518.001/T1518.001.md
  - https://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_security_software_discovery.yml
author: Daniil Yugoslavskiy, oscd.community, Huntrule Team
date: 2020-10-19
modified: 2022-11-27
tags:
  - attack.discovery
  - attack.t1518.001
logsource:
  category: process_creation
  product: linux
detection:
  selection:
    Image|endswith:
      - /grep
      - /egrep
    CommandLine|contains:
      - nessusd
      - td-agent
      - packetbeat
      - filebeat
      - auditbeat
      - osqueryd
      - cbagentd
      - falcond
  condition: selection
falsepositives:
  - Legitimate activities
level: low
license: DRL-1.1
related:
  - id: c9d8b7fd-78e4-44fe-88f6-599135d46d60
    type: derived