CVE-2026-59855

HIGH 8.6 PoC AVAILABLE ALL-YEARS

Published 2026-07-09 · Last modified 2026-07-14 · GitHub_M · NVD: Deferred

SiYuan is an open-source personal knowledge management system. Prior to 3.7.1, Asset.render in app/src/asset/index.ts interpolates the unsanitized this.path value into HTML assigned to innerHTML, allowing a crafted asset link containing a double quote to break out of the src attribute, inject an event handler, and execute JavaScript that can run OS commands in the Electron renderer. This issue is fixed in versions 3.7.1-alpha.2 and 3.7.1.

EXPLOIT AVAILABLE

Public exploit or PoC code exists. The barrier to attack is reduced — watch closely.

Exploitation likelihood

0.3%chance of exploitation in 30 days · 23rd percentile

○ In CISA KEV● Public exploit / PoC◆ SSVC: exploitation poc, automatable no

Impact if exploited

8.6CVSS 4.0 · HIGH · CNA

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
✓Privileges: No account or privileges required
⚠User interaction: Requires active user interaction
✓Complexity: No special conditions — reliably repeatable
✓Requirements: No special attack requirements

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-59855/poc.jsonMachine-readable PoC index for this CVE (for automation).

For defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-59855/poc.json

Affected

Vendors Siyuan Note

Products Siyuan

Weakness (CWE)

CWE-80: : Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

All CVSS metrics

HIGH 8.6 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
HIGH 8.6 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/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

References

Exploits & PoC

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-w3gq-5j72-36vc x_refsource_CONFIRMexploit

Technical & other

https://github.com/siyuan-note/siyuan/commit/efbe3a557720034782643e55c9e0282530cb6bbb x_refsource_MISC
https://github.com/siyuan-note/siyuan/releases/tag/v3.7.1 x_refsource_MISC

Sources: NVD · CVE.org · EPSS