Authentication Bypass in GitLab CE/EE due to Improper Input Sanitization
CVE-2026-15723

8.2HIGH

Key Information:

Vendor

Gitlab
Status
Gitlab
Vendor
CVE Published:
21 October 2026

What is CVE-2026-15723?

A vulnerability in GitLab CE/EE versions before 19.5.1 allows an authenticated user to potentially take over an existing account without user interaction. This occurs when OmniAuth SAML and LDAP auto-linking features are enabled, exposing the system to an exploitation path due to inadequate input sanitization during the LDAP email lookup process. Organizations utilizing these versions should apply the latest patches to mitigate this security risk.

Affected Version(s)

GitLab 10.1 < 19.3.6

GitLab 19.4 < 19.4.3

GitLab 19.5 < 19.5.1

References

https://gitlab.com/gitlab-org/gitlab/-/work_items/605977
https://hackerone.com/reports/3852192
technical-descriptionexploitpermissions-required
https://docs.gitlab.com/releases/patches/patch-release-gi...

CVSS V3.1

Score:
8.2
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
Low
User Interaction:
None
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Thanks [stealthy](https://hackerone.com/stealthy) for reporting this vulnerability through our HackerOne bug bounty program
.