CVE-2026-3254
Improper Restriction of Rendered UI Layers or Frames in GitLab
CVSS Score
3.5
EPSS Score
0.0%
EPSS Percentile
0th
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.11 before 18.11.1 that under certain conditions could have allowed an authenticated user to load unauthorized content into another user's browser due to improper input validation in the Mermaid sandbox.
| CWE | CWE-1021 |
| Vendor | gitlab |
| Product | gitlab |
| Ecosystems | |
| Industries | Technology |
| Published | Apr 22, 2026 |
| Last Updated | Apr 22, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
GitLab / GitLab
18.11 < 18.11.1
References
Credits
Thanks [joaxcar](https://hackerone.com/joaxcar) for reporting this vulnerability through our HackerOne bug bounty program