Incorrect Authorization in GitLab
Summary
| CVE | CVE-2026-16255 |
|---|---|
| State | PUBLISHED |
| Assigner | GitLab |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-22 01:16:59 UTC |
| Updated | 2026-11-04 23:10:00 UTC |
| 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. |
Risk And Classification
Primary CVSS: v3.1 7.1 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS: 0.002090000 probability, percentile 0.105070000 (date 2026-10-22)
Problem Types: CWE-863 | CWE-863 CWE-863: Incorrect Authorization
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
| 3.1 | [email protected] | Secondary | 5.9 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N |
| 3.1 | CNA | CVSS | 5.9 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| gitlab.com/gitlab-org/gitlab/-/work_items/606479 | [email protected] | gitlab.com | Permissions Required |
| docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-released | [email protected] | docs.gitlab.com | Release Notes, Vendor Advisory |
| hackerone.com/reports/3809350 | [email protected] | hackerone.com | Permissions Required |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Thanks [3nvz](https://hackerone.com/3nvz) for reporting this vulnerability through our HackerOne bug bounty program (en)
Additional Advisory Data
Solutions
CNA: Upgrade to versions 19.3.6, 19.4.3, 19.5.1 or above.
There are currently no legacy QID mappings associated with this CVE.