CVE-2026-40322CRITICAL 9.0EPSS p22.1%
CVE-2026-40322CVE-2026-40322
Description
SiYuan is an open-source personal knowledge management system. In versions 3.6.3 and below, Mermaid diagrams are rendered with securityLevel set to "loose", and the resulting SVG is injected into the DOM via innerHTML. This allows attacker-controlled javascript: URLs in Mermaid code blocks to survive into the rendered output. On desktop builds using Electron, windows are created with nodeIntegration enabled and contextIsolation disabled, escalating the stored XSS to arbitrary code execution when a victim opens a note containing a malicious Mermaid block and clicks the rendered diagram node. This issue has been fixed in version 3.6.4.
Scoring
| CVSS 3.1 | 9.0 (CRITICAL) |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H |
| EPSS | 0.31% probability of exploitation · percentile 22.1% · 2026-06-19T12:03:05Z |
| Published | 2026-04-16 |
| Last modified | 2026-04-20 |
Underlying weaknesses· 2
References
2
| Type | Target | Confidence | Tier |
|---|---|---|---|
| Weakness | Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')cwe-79 | 0% | live |
| Weakness | Improper Control of Generation of Code ('Code Injection')cwe-94 | 0% | live |
Related by meaning· 6
Nearest entities by semantic similarity across the cs-graph corpus.