Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) in GitLab

published 2025-06-12 16 mo ago modified 2026-06-17 4 mo ago also BIT-gitlab-2025-4278 , EUVD-2025-18169

cvss: 8.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 10.9%; EPSS 10.9% chance of exploitation in 30 days, percentile 95%
public exploits: 0; none known

An issue has been discovered in GitLab CE/EE affecting all versions starting with 18.0 before 18.0.2. Under certain conditions html injection in new search page could lead to account takeover.

Patch / fix

fixed in 2

bitnami gitlab 18.0.2
GitLab GitLab 18.0.2

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 16 mo ago (2025-06-12)

Exploit prediction

10.94% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

hackerone.com https://hackerone.com/reports/3085738 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
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	>=18.0.0, <18.0.2	18.0.2

Affected products

GitLab GitLab

Classification

Weakness

CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page

Technology feeds

GitLab rss critical rss

References

hackerone.com /reports/3085738
technical-description, exploit, permissions-required, web
gitlab.com /gitlab-org/gitlab/-/issues/539198
issue-tracking, permissions-required, broken-link, web
nvd.nist.gov /vuln/detail/CVE-2025-4278
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