CVE-2026-71285 json
Uptime Kuma Stored XSS via Matomo Analytics Site ID on Public Status Pages
published 3mo ago modified 19d ago also EUVD-2026-53370
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 32%
- public exploits
- 0
- none known
Summary
Uptime Kuma's Matomo analytics integration (server/analytics/matomo-analytics.js) injects the admin-configurable Matomo value as a bare, unquoted JavaScript expression inside a <script> block rendered on every public status page. A siteId value such as , once saved by an editor/admin, executes arbitrary JavaScript for every unauthenticated visitor of the public /status/<slug> page, enabling session-cookie theft and full page takeover.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 3mo ago
Exploit prediction
0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N |
Affected products
- louislam uptime-kuma
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/louislam/uptime-kuma
third-party-advisory
-
github.com
/louislam/uptime-kuma/blob/master/server/analytics/matomo-analytics.js
third-party-advisory
Sources
- CVE List CVE-2026-71285
- NVD CVE-2026-71285
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.