CVE-2026-92986: SiYuan before 3.8.4 Cross-Site Scripting via Document Title

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-17 · updated 2026-09-17
Weakness: CWE-79

Description

SiYuan before 3.8.4 renders document titles as HTML in the backlink dock tree without escaping markup characters. Attackers can set malicious titles through the rename API or crafted notebooks to execute scripts in the Electron renderer with access to child_process for command execution.

Affected products

siyuan-note siyuan: before 3.8.4 — fixed in 3.8.4

How to fix

Upgrade to a fixed version: siyuan-note siyuan 3.8.4. Check the vendor advisory for mitigations.

References

https://github.com/siyuan-note/siyuan
https://github.com/siyuan-note/siyuan/blob/v3.8.3/app/src/util/Tree.ts#L134
https://github.com/siyuan-note/siyuan/commit/6f093ebe50afc503e2a8b056164293054f8509e7
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-c5h9-g2c6-fxjw
https://www.vulncheck.com/advisories/siyuan-before-3.8.4-cross-site-scripting-via-document-title

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