CVE-2026-1090

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

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 10.6 before 18.7.6, 18.8 before 18.8.6, and 18.9 before 18.9.2 that could have allowed an authenticated user, when the `markdown_placeholders` feature flag was enabled, to inject JavaScript in a browser due to improper sanitization of placeholder content in markdown processing.

Affected

GitLab

CVSS v3.1 NVD

5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS v3.1 GITLAB

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

EPSS

0.24% chance of exploitation in the next 30 days, 14th percentile

Published

2026-03-11

Updated

2026-03-12

Proof-of-concept exploits (1)

• https://hackerone.com/reports/3502450

Security advisories

• https://about.gitlab.com/releases/2026/03/11/patch-release-gitlab-18-9-2-released

References

• CVE Record
• NVD entry