CVE-2026-16255
Received
Received - Intake
GitLab EE Membership Lock Bypass via SAML/LDAP
Vulnerability report for CVE-2026-16255, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-22
Last updated on: 2026-10-22
Assigner: GitLab Inc.
Description
Description
GitLab has remediated an issue in GitLab EE affecting all versions from 12.0 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that, when the instance-wide SAML or LDAP membership lock was enabled, an authenticated user could have granted or accepted project and group membership outside the identity provider's control, due to incomplete enforcement of the membership lock on requests created before the lock was enabled.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| GitLab | GitLab | 12.0 |
| GitLab | GitLab | 19.4 |
| GitLab | GitLab | 19.5 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-863 | The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. |