Vulnerability Report

CVE-2026-5173

Title: Improper Access Control via WebSockets

Other

Proof Of Concept

PoC Available for CVE-2026-5173

CWE Category CWE-749

Published Date Apr 08, 2026

Modified Date Apr 16, 2026

Exploit Status Available

Score 8.5 CVSS v3.1

Exploit Probability (EPSS)

0.03%

Vulnerability Summary

CVE-2026-5173: GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.9.6 before 18.8.9, 18.9 before 18.9.5, and 18.10 before 18.10.3 that could have allowed an authenticated user to invoke unintended server-side methods through websocket connections due to improper access control.

Impacted Vendors

gitlab 1

jenkins 1

Reference Links

https://about.gitlab.com/releases/2026/04/08/patch-release-gitlab-18-10-3-released/ https://gitlab.com/gitlab-org/gitlab/-/work_items/588959

CVSS v3.1

Source Entity [email protected]

Severity HIGH

8.5

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

CHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

Associated Attack Patterns (CAPEC)

Total: Patterns