CVE-2026-6267: GitLab Information Disclosure Vulnerability

CVE-2026-6267 Overview

GitLab has patched an information disclosure vulnerability in GitLab Community Edition (CE) and Enterprise Edition (EE). The flaw affects all versions from 10.1.0 before 19.0.5, 19.1 before 19.1.3, and 19.2 before 19.2.1. An authenticated user with the Developer role could access unauthorized information under certain conditions. The root cause is insufficient access controls on internal request handling, tracked as CWE-201: Insertion of Sensitive Information Into Sent Data.

Critical Impact
Authenticated Developer-role users can retrieve information they are not authorized to view, breaking project and group confidentiality boundaries in multi-tenant GitLab instances.

Affected Products

GitLab CE/EE versions 10.1.0 through 19.0.4
GitLab CE/EE versions 19.1 through 19.1.2
GitLab CE/EE versions 19.2 through 19.2.0

Discovery Timeline

2026-07-29 - CVE-2026-6267 published to NVD
2026-07-30 - Last updated in NVD database

Technical Details for CVE-2026-6267

Vulnerability Analysis

The vulnerability resides in how GitLab handles internal request processing. GitLab exposes internal endpoints used by Rails controllers, background workers, and service classes to fetch project and group resources. These internal request handlers did not consistently enforce the same authorization checks applied to external API and UI requests.

An authenticated user assigned the Developer role in one context could trigger these internal code paths to read data belonging to resources outside their permitted scope. The disclosed information may include source code, merge request metadata, pipeline data, and other project-scoped resources that Developer-role users typically cannot see across boundaries.

The attack requires valid GitLab credentials and Developer-level project membership, which raises the exploitation bar relative to unauthenticated flaws. However, Developer is one of the most commonly granted roles in enterprise GitLab deployments, expanding the practical attacker population.

Root Cause

The issue is an access control gap classified under CWE-201. Internal request handling code paths trusted the calling context and skipped granular per-resource authorization. When these code paths were reachable through user-influenced requests, the trust boundary between internal and external callers collapsed.

Attack Vector

Exploitation requires network access to the GitLab instance and an authenticated session with Developer role on at least one project. The attacker crafts requests that traverse the vulnerable internal request path to solicit data from resources they do not own. High attack complexity indicates that specific preconditions must align, but no user interaction is required from the victim. Successful exploitation impacts confidentiality, integrity, and availability, and can cross the security scope of the originating project.

Refer to the HackerOne Report #3658324 and GitLab Work Item #596606 for technical details.

Detection Methods for CVE-2026-6267

Indicators of Compromise

Unusual volumes of API requests from a single Developer-role user against project, group, or internal endpoints outside their normal project membership.
Access log entries where a user retrieves resources for projects on which they are not a listed member.
Repeated requests to internal or graph-based endpoints such as /api/v4/internal/* or GraphQL queries enumerating project IDs.

Detection Strategies

Correlate GitLab audit events with project membership data to flag reads of resources outside a user's authorized project set.
Baseline API request patterns per user and alert on sudden increases in cross-project resource access.
Enable and forward GitLab application, production_json.log, and audit logs to a central analytics platform for retrospective hunting.

Monitoring Recommendations

Monitor for Developer-role accounts issuing requests to endpoints associated with administrative or cross-project data.
Track authentication tokens, personal access tokens, and CI job tokens making atypical enumeration calls.
Alert on privilege boundary violations surfaced by GitLab audit events after upgrading to a fixed version that adds logging.

How to Mitigate CVE-2026-6267

Immediate Actions Required

Upgrade GitLab CE/EE to 19.0.5, 19.1.3, or 19.2.1 as applicable to your release branch.
Audit personal access tokens, deploy tokens, and CI job tokens for signs of misuse and rotate any tokens tied to suspicious activity.
Review project and group membership to remove unnecessary Developer-role assignments and enforce least privilege.

Patch Information

GitLab addressed the vulnerability in the GitLab Patch Release 19.2.1, along with backports to the 19.0.5 and 19.1.3 maintenance branches. Self-managed operators should apply the patch that matches their current major.minor version. GitLab.com is patched by the vendor.

Workarounds

No official workaround is published; upgrading to a fixed release is the required remediation.
Restrict network access to self-managed GitLab instances to trusted users while planning the upgrade.
Temporarily reduce Developer-role grants and rely on Reporter or Guest roles where feasible until patching is complete.

bash

# Example upgrade commands for self-managed GitLab (Omnibus)
sudo apt-get update
sudo apt-get install gitlab-ee=19.2.1-ee.0
sudo gitlab-ctl reconfigure
sudo gitlab-rake gitlab:check SANITIZE=true