Windows: Root Certificate Added Using certutil.exe -addstore
Flags certutil.exe executions that use -addstore with root-related parameters to install a certificate.
- Product
- windows
- Category
- process_creation
- Author
- oscd.community, @redcanary, Zach Stanford @svch0st (SigmaHQ), DRL 1.1
- Published
- 2023-03-05
- 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 identifies Windows process executions of certutil.exe that include the -addstore flag and specify the root certificate store. Installing a root certificate can enable an attacker to reduce browser or TLS warning prompts when intercepting or proxying traffic to adversary-controlled sites. It relies on process creation telemetry, matching the image path/OriginalFileName and filtering on command-line content.
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: "Windows: Root Certificate Added Using certutil.exe -addstore"
id: 05e7dc88-93ec-4885-8530-fe3f94d20863
related:
- id: 42821614-9264-4761-acfc-5772c3286f76
type: derived
- id: 46591fae-7a4c-46ea-aec3-dff5e6d785dc
type: obsolete
- id: d2125259-ddea-4c1c-9c22-977eb5b29cf0
type: derived
status: test
description: This rule identifies Windows process executions of certutil.exe that include the -addstore flag and specify the root certificate store. Installing a root certificate can enable an attacker to reduce browser or TLS warning prompts when intercepting or proxying traffic to adversary-controlled sites. It relies on process creation telemetry, matching the image path/OriginalFileName and filtering on command-line content.
references:
- https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1553.004/T1553.004.md
- https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_certutil_certificate_installation.yml
author: oscd.community, @redcanary, Zach Stanford @svch0st, Huntrule Team
date: 2023-03-05
modified: 2024-03-05
tags:
- attack.defense-impairment
- attack.t1553.004
logsource:
category: process_creation
product: windows
detection:
selection_img:
- Image|endswith: \certutil.exe
- OriginalFileName: CertUtil.exe
selection_cli_add:
CommandLine|contains|windash: -addstore
selection_cli_store:
CommandLine|contains: root
condition: all of selection_*
falsepositives:
- Help Desk or IT may need to manually add a corporate Root CA on occasion. Need to test if GPO push doesn't trigger FP
level: medium
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_certutil_certificate_installation/info.yml
license: DRL-1.1