What is CVE-2026-33203?

CVE-2026-33203 is a high-severity vulnerability in Siyuan-note Siyuan, classified under CWE-248. CVSS score: 7.5/10. Published 2026-03-20.

How severe is CVE-2026-33203?

High severity. CVSS v3 base score is 7.5 out of 10.

Auth bypass in Siyuan-note Siyuan

CVE-2026-33203

SiYuan is a personal knowledge management system. Prior to version 3.6.2, the SiYuan kernel WebSocket server accepts unauthenticated connections when a specific "auth keepalive" query parameter is present. After connection, incoming messag…

EPSS: 0.001 (21.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Siyuan-note Siyuan — versions < 3.6.2

Weakness classification (CWE)

CWE-248
CWE-306 — Missing Authentication for Critical Function

References

https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3g9h-9hp4-654v (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-33203?: CVE-2026-33203 is a high-severity vulnerability in Siyuan-note Siyuan, classified under CWE-248. CVSS score: 7.5/10. Published 2026-03-20.
How severe is CVE-2026-33203?: High severity. CVSS v3 base score is 7.5 out of 10.