CVE-2026-75917
CRITICAL 9.3 PoC AVAILABLESiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 6th percentile
Impact if exploited
9.3CVSS 4.0 · CRITICAL
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ✓Privileges: No account or privileges required
- ⚠User interaction: Succeeds with passive user activity
- ✓Complexity: No special conditions — reliably repeatable
- ✓Requirements: No special attack requirements
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jjq3-3942-x99r
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-75917/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-75917/poc.json
Weakness (CWE)
- CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSS vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
All CVSS metrics
- CRITICAL 9.3 v4.0 · CNA Primary
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - HIGH 8.6 v3.1 · CNA Primary
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - CRITICAL 9.3 v4.0 · NVD Secondary
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 - HIGH 8.6 v3.1 · NVD Secondary
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H