CVE-2026-34585SiYuan: Stored XSS in imported .sy.zip content leads to arbitrary command execution
- 8.6HighCVSS base score
- 0.35%Exploitation in 30 daysEPSS · top 71% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
SiYuan is a personal knowledge management system. Prior to version 3.6.2, a vulnerability allows crafted block attribute values to bypass server-side attribute escaping when an HTML entity is mixed with raw special characters. An attacker can embed a malicious IAL value inside a .sy document, package it as a .sy.zip, and have the victim import it through the normal Import -> SiYuan .sy.zip workflow. Once the note is opened, the malicious attribute breaks out of its original HTML context and injects an event handler, resulting in stored XSS. In the Electron desktop client, this XSS reaches remote code execution because injected JavaScript runs with access to Node/Electron APIs. This issue has been patched in version 3.6.2.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-ff66-236v-p4fg (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 1 day later
· 1 day later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | High8.2 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.35% · top 71% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
- affected < 3.6.2
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/siyuan-note/siyuan/kernelGHSA-ff66-236v-p4fg (opens in a new tab)
References
References3
- https://github.com/siyuan-note/siyuan/security/advisories/GHSA-ff66-236v-p4fg (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/siyuan-note/siyuan/issues/17246 (opens in a new tab)x_refsource_MISC
- https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-17685 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-ff66-236v-p4fg (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-34585)Record last updated .