GitLab CE/EE, versions 10.3 up to 11.x before 11.3.11, 11.4 before 11.4.8, and 11.5 before 11.5.1, are vulnerable to an XSS vulnerability in Markdown fields via Mermaid.
Severity
CVSS 3.1
5.4 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS
0.9% chance of exploitation in the next 30 days; higher than 60% of CVEs (scores of 2026-10-31)