Linux: Process executing update-ca-certificates or update-ca-trust
Detects Linux executions of update-ca-certificates or update-ca-trust that install new trusted root certificates.
- Product
- linux
- Category
- process_creation
- Author
- Ömer Günal, oscd.community (SigmaHQ), DRL 1.1
- Published
- 2020-10-05
- Updated
- 2026-07-31
ATT&CK techniques
Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags execution of the Linux certificate trust update utilities /update-ca-certificates or /update-ca-trust, which results in installation of new trusted certificates system-wide. Attackers may abuse this behavior to establish trust for attacker-controlled endpoints and reduce browser or client warnings when connecting to C2 or other infrastructure. The detection relies on process creation telemetry that captures the executed command path ending with either of those utilities.
Reporting behind it
Changelog
v2- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Linux: Process executing update-ca-certificates or update-ca-trust"
id: 10c1146d-0002-430d-8aae-573303067250
status: test
description: This rule flags execution of the Linux certificate trust update utilities /update-ca-certificates or /update-ca-trust, which results in installation of new trusted certificates system-wide. Attackers may abuse this behavior to establish trust for attacker-controlled endpoints and reduce browser or client warnings when connecting to C2 or other infrastructure. The detection relies on process creation telemetry that captures the executed command path ending with either of those utilities.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1553.004/T1553.004.md
- https://github.com/SigmaHQ/sigma/blob/master/rules/linux/process_creation/proc_creation_lnx_install_root_certificate.yml
author: Ömer Günal, oscd.community, Huntrule Team
date: 2020-10-05
modified: 2022-07-07
tags:
- attack.defense-impairment
- attack.t1553.004
logsource:
product: linux
category: process_creation
detection:
selection:
Image|endswith:
- /update-ca-certificates
- /update-ca-trust
condition: selection
falsepositives:
- Legitimate administration activities
level: low
license: DRL-1.1
related:
- id: 78a80655-a51e-4669-bc6b-e9d206a462ee
type: derived