CVE-2026-86016 json
VNote: Stored XSS via YAML Frontmatter Leading to Local File Read and Remote Exfiltration
published 2026-10-13 26 d ago modified 2026-10-29 10 d ago also EUVD-2026-100522
- cvss
- 8.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 20%
- public exploits
- 0
- none known
Summary
VNote is a note-taking platform. Prior to 4.3.0, VNote uses the assignment `preNode.innerHTML = p_metaData` in src/data/extra/web/js/markdownit.js to insert YAML frontmatter metadata into a pre element before the protectFromXss sanitization path runs. Opening an attacker-supplied Markdown note can therefore execute stored JavaScript in the file:// viewer context. Because QWebEngineSettings::LocalContentCanAccessRemoteUrls enables local content to access remote URLs, the script can read reachable local note files and transmit their contents to a remote server without further interaction after the note is opened. This issue is fixed in version 4.3.0.
Patch / fix
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 10 d ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/vnotex/vnote/security/advisories/GHSA-vfhj-c636-h59x referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N |
Affected products
- vnotex vnote
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
Sources
- CVE List CVE-2026-86016
- NVD CVE-2026-86016
Fencer Vulns 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.