CVE-2026-3254 (GCVE-0-2026-3254)

Vulnerability from cvelistv5 – Published: 2026-04-22 16:29 – Updated: 2026-04-22 17:39
VLAI?
Title
Improper Restriction of Rendered UI Layers or Frames in GitLab
Summary
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.
Severity ?
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
CWE
  • CWE-1021 - Improper Restriction of Rendered UI Layers or Frames
Assigner
References
Impacted products
Vendor Product Version
GitLab GitLab Affected: 18.11 , < 18.11.1 (semver)
    cpe:2.3:a:gitlab:gitlab:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Thanks [joaxcar](https://hackerone.com/joaxcar) for reporting this vulnerability through our HackerOne bug bounty program
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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