What is CVE-2026-41421?

CVE-2026-41421 is a high-severity vulnerability in Siyuan-note Siyuan, classified under OS Command Injection. CVSS score: 8.8/10. Published 2026-04-24.

How severe is CVE-2026-41421?

High severity. CVSS v3 base score is 8.8 out of 10.

RCE in Siyuan-note Siyuan

CVE-2026-41421

SiYuan is an open-source personal knowledge management system. Prior to 3.6.5, SiYuan desktop renders notification messages as raw HTML inside an Electron renderer. The notification route POST /api/notification/pushMsg accepts a user-contr…

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.000 (10.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

Siyuan-note Siyuan — versions < 3.6.5

Weakness classification (CWE)

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-grjj-6f6g-cq8q (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-41421?: CVE-2026-41421 is a high-severity vulnerability in Siyuan-note Siyuan, classified under OS Command Injection. CVSS score: 8.8/10. Published 2026-04-24.
How severe is CVE-2026-41421?: High severity. CVSS v3 base score is 8.8 out of 10.