What is CVE-2026-100644?

CVE-2026-100644 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under SQL Injection. CVSS score: 7.5/10. Published 2026-09-26.

How severe is CVE-2026-100644?

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

SQL Injection in Siyuan-Note Siyuan

CVE-2026-100644

SiYuan before v3.8.4 contains a SQL injection vulnerability in the graph query endpoint where the dailyNoteSavePath parameter is concatenated into SQL without escaping. Unauthenticated attackers on published sites with auth disabled can inject SQL via UNION SELECT to extract arbitrary database rows from all notebooks.

Vulnerability class: SQL Injection

Published 2026-09-26 · last modified 2026-09-26.

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:H/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Siyuan-Note Siyuan

Weakness classification (CWE)

CWE-89 — SQL Injection

References

github.com/siyuan-note/siyuan/security/advisories/GHSA-xr4h-j7cg-q8pc (vendor-advisory)
www.vulncheck.com/advisories/siyuan-before-3.8.4-sql-injection-via-dailynotesav… (third-party-advisory)

Frequently asked questions

What is CVE-2026-100644?: CVE-2026-100644 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under SQL Injection. CVSS score: 7.5/10. Published 2026-09-26.
How severe is CVE-2026-100644?: High severity. CVSS v3 base score is 7.5 out of 10.