CVE-2026-84739

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 13.11 before 19.2.7, 19.3 before 19.3.3, and 19.4 before 19.4.1 that under certain conditions could have allowed an authenticated user to execute arbitrary JavaScript in the context of another user's browser session due to improper sanitization of path components in the merge request diff viewer.

CVSS 3.1

8.7CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

EPSS

0.3% chance of exploitation in the next 30 days; higher than 27% of CVEs (scores of 2026-10-25)

CWE

CWE-79

Published

2026-09-29

Modified

2026-10-05

Record from

the NVD, synced 2026-10-19

Affected

• gitlab:gitlab

References

• https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-4-1-released/
• https://gitlab.com/gitlab-org/gitlab/-/work_items/627316
• https://hackerone.com/reports/3938482

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