# CVE-2026-16255: Incorrect Authorization in GitLab

> CVE-2026-16255: Incorrect Authorization in GitLab. CVSS 5.9 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-16255
Last updated: 2026-10-22T16:18:19Z

- Published: 2026-10-21 23:35 UTC · Updated: 2026-10-22 16:18 UTC · Assigner: GitLab
- CVSS: 5.9 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N
- EPSS: 0.21%, 11th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-863

## 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.

## Affected vendors and products

- GitLab: GitLab

## Tracked companies

- [GitLab](https://rewindex.com/company/gitlab.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-16255)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-16255)
- [https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-released/](https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-released/)
- [https://gitlab.com/gitlab-org/gitlab/-/work\_items/606479](https://gitlab.com/gitlab-org/gitlab/-/work_items/606479)
- [https://hackerone.com/reports/3809350](https://hackerone.com/reports/3809350)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-16255 · Markdown: https://rewindex.com/cve/CVE-2026-16255.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-16255 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:04:10.865Z