Vulnerability · Published Dec 11, 2025 · Assigned by GitLab
CVE-2025-8405Improper Encoding or Escaping of Output in GitLab
High 7.7
In plain English
A high-severity security flaw in GitLab from GitLab. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).
Severity (CVSS 3.1)7.7High
Exploit odds (30 days)0.5%top 56.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
Weakness: CWE-116 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N
References
- GitLab Issue #558214 issue-tracking, permissions-required
- HackerOne Bug Bounty Report #3270940 technical-description, exploit, permissions-required
- https://about.gitlab.com/releases/2025/12/10/patch-release-gitlab-18-6-2-released/