CVE-2026-5173
Improper Access Control in GitLab Websocket Enables Unauthorized Actions
Publication date: 2026-04-08
Last updated on: 2026-04-16
Assigner: GitLab Inc.
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| gitlab | gitlab | From 18.9.0 (inc) to 18.9.5 (exc) |
| gitlab | gitlab | From 18.10.0 (inc) to 18.10.3 (exc) |
| gitlab | gitlab | From 16.9.6 (inc) to 18.8.9 (exc) |
| gitlab | gitlab | From 18.10.0 (inc) to 18.10.3 (exc) |
| gitlab | gitlab | From 18.9.0 (inc) to 18.9.5 (exc) |
| gitlab | gitlab | From 16.9.6 (inc) to 18.8.9 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-749 | The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in GitLab CE/EE versions from 16.9.6 before 18.8.9, 18.9 before 18.9.5, and 18.10 before 18.10.3 allows an authenticated user to invoke unintended server-side methods through websocket connections. This happens due to improper access control, meaning the system does not correctly restrict what actions authenticated users can perform via websockets.
How can this vulnerability impact me? :
The impact of this vulnerability is that an authenticated user could execute server-side methods that they are not supposed to access. This could lead to unauthorized actions being performed on the server, potentially compromising the confidentiality and integrity of data, as indicated by the CVSS score showing high confidentiality impact and low integrity impact.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade GitLab CE/EE to a fixed version. Specifically, update to versions 18.8.9 or later if you are using the 16.9.6 to before 18.8.9 range, 18.9.5 or later if you are using versions before 18.9.5, or 18.10.3 or later if you are using versions before 18.10.3.
This will prevent authenticated users from invoking unintended server-side methods through websocket connections due to improper access control.