Vulnerability Details CVE-2026-32308
OneUptime is a solution for monitoring and managing online services. Prior to 10.0.23, the Markdown viewer component renders Mermaid diagrams with securityLevel: "loose" and injects the SVG output via innerHTML. This configuration explicitly allows interactive event bindings in Mermaid diagrams, enabling XSS through Mermaid's click directive which can execute arbitrary JavaScript. Any field that renders markdown (incident descriptions, status page announcements, monitor notes) is vulnerable. This vulnerability is fixed in 10.0.23.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 9.0%
CVSS Severity
CVSS v3 Score 7.6