CVE-2025-8405
Improper Encoding or Escaping of Output in GitLab
GitLab has remediated a security issue in GitLab CE/EE affecting all versions from 17.1 before 18.4.6, 18.5 before 18.5.4, and 18.6 before 18.6.2 that could have allowed an authenticated user to perform unauthorized actions on behalf of other users by injecting malicious HTML into vulnerability code flow displays.
Fixes and workarounds
Fix
Upgrade to versions 18.4.6, 18.5.4, 18.6.2 or above.
Source: CNA: GitLabAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| GitLab GitLab |
≥ 17.1; < 18.4.6 (affected, semver) ≥ 18.5; < 18.5.4 (affected, semver) ≥ 18.6; < 18.6.2 (affected, semver) Other versions: unaffected |
CNA: GitLab |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 7.7 high |
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N | CNA: GitLab |
Exploit evidence
- https://hackerone.com/reports/3270940
exploit · CNA: GitLab
References
- https://gitlab.com/gitlab-org/gitlab/-/issues/558214CNA: GitLab · issue-tracking, permissions-required
- https://hackerone.com/reports/3270940CNA: GitLab · technical-description, exploit, permissions-required
- https://about.gitlab.com/releases/2025/12/10/patch-release-gitlab-18-6-2-released/CNA: GitLab
For agents and automation
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Endpoints and access details
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