CVE-2026-32308: high-severity vulnerability in oneuptime
OneUptime: Stored XSS via Mermaid Diagram Rendering (securityLevel: "loose")
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.6epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
Affected products
OneUptime · oneuptimeRelated CVEs — oneuptime
In the same product, most dangerous first.
CVE-2026-27728CRITICALOneUptime: OS Command Injection in Probe NetworkPathMonitor via unsanitized destination in traceroute exec()EPSS 2.0%CVE-2026-30957CRITICALOneUptime Synthetic Monitor RCE via exposed Playwright browser objectEPSS 1.3%CVE-2026-30958HIGHOneUptime: Path Traversal — Arbitrary File Read (No Auth)EPSS 1.2%CVE-2026-33396CRITICALOneUptime has sandbox escape in Synthetic Monitor Playwright runtime allows project members to execute arbitrary commands on ProbeEPSS 0.8%CVE-2026-32306CRITICALOneUptime ClickHouse SQL Injection via Aggregate Query ParametersEPSS 0.7%CVE-2024-29194HIGHOneUptime Vulnerable to a Privilege Escalation via Local Storage Key ManipulationEPSS 0.7%