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CVE-2026-32308GHSA-WVH5-6VJM-23QH

OneUptime: Stored XSS via Mermaid Diagram Rendering (securityLevel: "loose")

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 10.0.23
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: poc
  • Automatable: no
  • Technical impact: partial

Summary

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.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: poc · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • OneUptime oneuptime

    fixed in 10.0.23

  • oneuptimenpm

    fixed in 10.0.23

References 1

GitHub · OneUptime/oneuptime