What is CVE-2026-40259?

CVE-2026-40259 is a high-severity vulnerability in Siyuan-note Siyuan, classified under Improper Authorization. CVSS score: 8.1/10. Published 2026-04-16.

How severe is CVE-2026-40259?

High severity. CVSS v3 base score is 8.1 out of 10.

Auth bypass in Siyuan-note Siyuan

CVE-2026-40259

SiYuan is an open-source personal knowledge management system. In versions 3.6.3 and below, the /api/av/removeUnusedAttributeView endpoint is protected only by generic authentication that accepts publish-service RoleReader tokens. The hand…

EPSS: 0.000 (9.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.

Affected products

Siyuan-note Siyuan — versions < 0.0.0-20260407035653-2f416e5253f1, < 3.6.4

Weakness classification (CWE)

CWE-285 — Improper Authorization

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-7m5h-w69j-qggg (x_refsource_CONFIRM)
https://github.com/siyuan-note/siyuan/releases/tag/v3.6.4 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-40259?: CVE-2026-40259 is a high-severity vulnerability in Siyuan-note Siyuan, classified under Improper Authorization. CVSS score: 8.1/10. Published 2026-04-16.
How severe is CVE-2026-40259?: High severity. CVSS v3 base score is 8.1 out of 10.