CVE-2025-12734 json
Improper Encoding or Escaping of Output in GitLab
published 11mo ago modified 28d ago also BIT-gitlab-2025-12734 , EUVD-2025-202668
- cvss
- 3.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 15.6 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, under certain conditions, render content in dialogs to other users by injecting malicious HTML content into merge request titles.
Patch / fix
- bitnami gitlab 18.4.6, 18.5.4, 18.6.2
- GitLab GitLab 18.4.6, 18.5.4, 18.6.2
Is CVE-2025-12734 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 11mo ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- hackerone.com https://hackerone.com/reports/3379381 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N |
| OSV | 3.1 | 3.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| bitnami | gitlab | >=15.6.0, <18.4.6 >=18.5.0, <18.5.4 >=18.6.0, <18.6.2 |
18.4.6 18.5.4 18.6.2 |
Affected products
- GitLab GitLab
Classification
- Weakness
-
- CWE-116 Improper Encoding or Escaping of Output
- Technology feeds
References
-
hackerone.com
/reports/3379381
technical-description, exploit, permissions-required, web
-
about.gitlab.com
/releases/2025/12/10/patch-release-gitlab-18-6-2-released/
release-notes, vendor-advisory, advisory
-
gitlab.com
/gitlab-org/gitlab/-/issues/579573
issue-tracking, permissions-required, broken-link, web
-
nvd.nist.gov
/vuln/detail/CVE-2025-12734
web
Sources
- CVE List CVE-2025-12734
- NVD CVE-2025-12734
- OSV BIT-gitlab-2025-12734
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.