XSS in GitLab

CVE-2025-4439

An issue has been discovered in GitLab CE/EE affecting all versions from 15.10 before 18.0.5, 18.1 before 18.1.3, and 18.2 before 18.2.1 that could have allowed an authenticated user to perform cross-site scripting attacks when the instance is served through certain content delivery networks.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (14.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 14.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-4439: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000

Affected products

  • GitLab — versions 15.10, 18.1, 18.2

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-4439?
CVE-2025-4439 is a high-severity vulnerability in GitLab, classified under Cross-site Scripting. CVSS score: 7.7/10. Published 2025-07-23.
How severe is CVE-2025-4439?
High severity. CVSS v3 base score is 7.7 out of 10.
Is CVE-2025-4439 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.