CVE-2026-13151 Overview
CVE-2026-13151 is an improper authorization vulnerability [CWE-863] in GitLab Enterprise Edition (EE). The flaw affects all versions from 16.10 before 18.11.7, 19.0 before 19.0.4, and 19.1 before 19.1.2. Under certain conditions, an authenticated user can modify group-level settings beyond their intended permissions. GitLab has remediated the issue in patched releases.
Critical Impact
An authenticated attacker with elevated privileges on the instance can bypass group-level authorization controls to alter settings they should not be able to change, resulting in limited integrity impact to group configuration.
Affected Products
- GitLab EE versions 16.10 through 18.11.6
- GitLab EE versions 19.0 through 19.0.3
- GitLab EE versions 19.1 through 19.1.1
Discovery Timeline
- 2026-07-08 - CVE-2026-13151 published to NVD
- 2026-07-08 - Last updated in NVD database
Technical Details for CVE-2026-13151
Vulnerability Analysis
The vulnerability stems from improper authorization enforcement in GitLab EE's group-level settings handling. GitLab groups apply role-based access control to determine which members can view or modify configuration. Under specific conditions, the authorization check does not correctly validate the acting user's permissions against the target group setting. An authenticated user with elevated privileges can then modify configuration values reserved for higher-privileged roles.
The issue is classified under [CWE-863] Incorrect Authorization. It requires authentication and network access to the GitLab instance, and the attacker must already hold high privileges. Confidentiality and availability are not affected; only integrity of group-level settings is impacted, and only to a limited extent. EPSS data indicates a low probability of exploitation in the near term.
Root Cause
The root cause is missing or incomplete authorization logic in the code path that processes group-level setting updates. GitLab's policy layer failed to consistently verify that the acting user held the required role for the specific setting being modified, allowing certain elevated but non-owner users to bypass intended restrictions.
Attack Vector
An authenticated attacker sends a crafted API or UI request to modify a group-level setting they should not be permitted to change. Because the vulnerability is network-accessible and low-complexity, no user interaction from a victim is required. Exploitation is limited to modifying settings within groups where the attacker already has some level of privileged membership.
No public proof-of-concept, exploit code, or CISA KEV listing is available for this issue. See the GitLab Work Item Details for GitLab's technical description.
Detection Methods for CVE-2026-13151
Indicators of Compromise
- Unexpected changes to group-level settings in GitLab audit events, especially by users below the Owner role.
- API requests to group settings endpoints originating from accounts that historically only perform code or issue activity.
- Audit log entries showing setting modifications without a corresponding Owner-role approval workflow.
Detection Strategies
- Enable and centralize GitLab audit events for group-level setting changes, including group_updated, integration changes, and permission modifications.
- Baseline expected administrative actors per group and alert on setting changes performed by users outside that baseline.
- Correlate GitLab audit events with authentication logs to identify sessions where privilege usage deviates from historical patterns.
Monitoring Recommendations
- Forward GitLab audit and application logs to a centralized SIEM or data lake for retention and correlation.
- Alert on repeated 200-response PUT/PATCH requests to /api/v4/groups/:id from non-Owner accounts.
- Review group membership and role assignments regularly to reduce the population of users with elevated but non-Owner privileges.
How to Mitigate CVE-2026-13151
Immediate Actions Required
- Upgrade GitLab EE to 18.11.7, 19.0.4, or 19.1.2 or later, matching your current release branch.
- Audit recent group-level setting changes across all groups since the earliest affected version was deployed.
- Review and reduce the number of users holding Maintainer or higher roles in sensitive groups.
Patch Information
GitLab has released fixed versions 18.11.7, 19.0.4, and 19.1.2 that correct the authorization check. Refer to the GitLab Patch Release Notes for upgrade instructions and full release details.
Workarounds
- No official workaround has been published; upgrading to a fixed version is the required remediation.
- As an interim measure, restrict Maintainer-level membership in sensitive groups until patching is complete.
- Enable audit event streaming so that any unauthorized setting modification is captured for later review.
# Configuration example: verify installed GitLab version after upgrade
sudo gitlab-rake gitlab:env:info | grep "GitLab information" -A 5
# Omnibus package upgrade (Debian/Ubuntu)
sudo apt-get update && sudo apt-get install gitlab-ee=19.1.2-ee.0
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
