CVE-2026-16255: GitLab · Incorrect Authorization
Affects GitLabSource CVE Database V5
Not known to be exploited · CVSS 5.9 Medium · fixed in 19.5.1 : update GitLab when convenient.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 19.5.1, 19.4.3, 19.3.6
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 21 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade GitLab to 19.5.1, 19.4.3 or 19.3.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| GitLabGitLab | Affected
| Fixed in
|
| GitLabGitLab | Affected
| Fixed in
|
| GitLabGitLab | Affected
| Fixed in
|
CPE configurations (1)
cpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*
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.