CVE-2026-87814 json
SiYuan before v3.8.2 Stored XSS via Asset Preview
published 2mo ago modified last mo. also EUVD-2026-74840 , GHSA-64gp-333q-mq6j
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository siyuan-note/siyuan. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 7.3
- 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 30%
- public exploits
- 0
- none known
Summary
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in the search asset preview feature that fails to escape indexed asset content before inserting it into the DOM using innerHTML. Attackers who can place crafted text assets in a workspace can execute JavaScript in the SiYuan origin when victims preview the assets, enabling authenticated API requests and workspace manipulation.
Patch / fix
- siyuan-note siyuan 3.8.2
Is CVE-2026-87814 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- last mo.
Exploit prediction
0.37% chance of exploitation in the next 30 days, higher than 30% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N |
| CNA | 4.0 | 8.4 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- siyuan-note siyuan
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/siyuan-note/siyuan/security/advisories/GHSA-64gp-333q-mq6j
vendor-advisory, advisory
-
vulncheck.com
/advisories/siyuan-before-3.8.2-stored-xss-via-asset-preview
third-party-advisory
Sources
- CVE List CVE-2026-87814
- NVD CVE-2026-87814
- Maintainer advisory GHSA-64gp-333q-mq6j
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.
The maintainers of siyuan-note/siyuan published their own advisory on GitHub. Reviewed sources take precedence over it.