CVE-2026-32308
OneUptime: Stored XSS via Mermaid Diagram Rendering (securityLevel: "loose")
- State
- Published
- Severity
- 7.6 High
- Published
- Mar 12, 2026
- Updated
- Mar 14, 2026
- Reserved
- Mar 11, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.6 High | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N | GitHub_M |
Weaknesses
- CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Products
| Product | Versions |
|---|---|
oneuptimeOneUptime |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.