CVE-2026-87812 json
SiYuan before v3.8.2 Stored XSS via Bazaar iconURL
published 2mo ago modified 2mo ago also EUVD-2026-74838 , GHSA-rvcf-q4h8-w6c9
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
- 6.8
- 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 Bazaar package cards where the iconURL metadata is inserted directly into HTML img src attributes without escaping. Attackers can inject malicious URLs with event handlers that execute JavaScript in the authenticated SiYuan origin when users view Bazaar listings, enabling API requests and application state manipulation.
Patch / fix
- siyuan-note siyuan 3.8.2
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.36% 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 | 7.4 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N |
| CNA | 4.0 | 7.4 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/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-rvcf-q4h8-w6c9
vendor-advisory, advisory
-
vulncheck.com
/advisories/siyuan-before-3.8.2-stored-xss-via-bazaar-iconurl
third-party-advisory
Sources
- CVE List CVE-2026-87812
- NVD CVE-2026-87812
- Maintainer advisory GHSA-rvcf-q4h8-w6c9
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.