Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab

published 2025-03-27 19 mo ago modified 2026-09-10 59 d ago also BIT-gitlab-2025-2255 , EUVD-2025-8413

cvss: 8.7; 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 22%
public exploits: 0; none known

An issue has been discovered in Gitlab EE/CE for AppSec affecting all versions from 13.5.0 before 17.8.6, 17.9 before 17.9.3, and 17.10 before 17.10.1. Certain error messages could allow Cross-Site Scripting attacks (XSS). for AppSec.

Patch / fix

fixed in 2

bitnami gitlab 17.10.1
GitLab GitLab 17.8.6, 17.9.3, 17.10.1

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 19 mo ago (2025-03-27)

Exploit prediction

0.30% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

hackerone.com https://hackerone.com/reports/2994150 referenced PoC, tagged "exploit" by a source, unverified
gitlab.com https://gitlab.com/gitlab-org/gitlab/-/issues/524635 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
NVD	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
OSV	3.1	8.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Affected packages

ecosystem	package	affected	fixed in
bitnami	gitlab	>=13.5.0, <17.10.1	17.10.1

Affected products

GitLab GitLab

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

Technology feeds

GitLab rss critical rss

References

hackerone.com /reports/2994150
technical-description, exploit, permissions-required, web
gitlab.com /gitlab-org/gitlab/-/issues/524635
issue-tracking, permissions-required, exploit, evidence
nvd.nist.gov /vuln/detail/CVE-2025-2255
web

Sources

Fencer Vulns 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.

Summary