CVE-2025-12734

Description

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.

CVSS v3.1 Score

3.5

LOW

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

Weakness Type (CWE)

CWE-116 CWE-116

Affected Products

Vendor	Product	Versions
gitlab	gitlab	15.6.0 — 18.4.6
gitlab	gitlab	15.6.0 — 18.4.6
gitlab	gitlab	18.5.0 — 18.5.4
gitlab	gitlab	18.5.0 — 18.5.4
gitlab	gitlab	18.6.0 — 18.6.2
gitlab	gitlab	18.6.0 — 18.6.2

References

Advisories & Patches

https://about.gitlab.com/releases/2025/12/10/patch-release-gitlab-18-6-2-released/

Other References

https://gitlab.com/gitlab-org/gitlab/-/issues/579573 https://hackerone.com/reports/3379381

Frequently Asked Questions

What is CVE-2025-12734? +

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. It has a CVSS v3.1 base score of 3.5 (LOW).

How severe is CVE-2025-12734? +

CVE-2025-12734 has a CVSS v3.1 score of 3.5 out of 10, rated LOW. This is a low-severity vulnerability with limited impact.

What products are affected by CVE-2025-12734? +

CVE-2025-12734 affects products from gitlab, specifically: gitlab. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-12734? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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