Read the docs
TI-2026-24836 Aliases CVE-2026-32308GHSA-wvh5-6vjm-23qh

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

Priority HIGH 66CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00263 18th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed oneuptime (OneUptime): 10.0.23oneuptime (npm): 10.0.23

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OneUptimeoneuptimebefore 10.0.2310.0.23Patch availableCNA
—oneuptime (npm)before 10.0.2310.0.23Patch availableGHSA-wvh5-6vjm-23qh
  • oneuptime VendorOneUptime Affected before 10.0.23 Fixed in 10.0.23 Patch available CNA
  • oneuptime (npm) Vendor— Affected before 10.0.23 Fixed in 10.0.23 Patch available GHSA-wvh5-6vjm-23qh

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:hackerbay:oneuptime:*:*:*:*:*:*:*:*before 10.0.23VulnerableOneUptime
  • cpe:2.3:a:hackerbay:oneuptime:*:*:*:*:*:*:*:* Versions before 10.0.23 Vulnerable ·OneUptime

Remediation

  • Fix · CNA oneuptime (OneUptime) Fixed in 10.0.23
  • Fix · GHSA-wvh5-6vjm-23qh oneuptime (npm) Fixed in 10.0.23 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32308
  2. 2026-10-03 Alias added: GHSA-wvh5-6vjm-23qh

References

Exploit 1

Advisory 1

Other 2

  • TI-2026-22090 OneUptime: OS Command Injection in Probe NetworkPathMonitor via unsanitized destination in traceroute exec() CVSS 3.1CRITICAL 10.0
  • TI-2026-27002 OneUptime: Missing Authentication on Notification Endpoints CVSS 3.1CRITICAL 9.1
  • TI-2026-25573 OneUptime: WhatsApp Webhook Missing Signature Verification CVSS 4.0HIGH 8.7
  • TI-2025-40534 OneUptime Unauthorized User Creation via API CVSS 4.0HIGH 8.8
  • TI-2026-25793 Protection mechanism failure in oneuptime CVSS 3.1CRITICAL 10.0
  • TI-2026-24835 OneUptime ClickHouse SQL Injection via Aggregate Query Parameters CVSS 3.1CRITICAL 10.0
See all 22 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences