Auth bypass in Siyuan-Note Siyuan

CVE-2026-73605

SiYuan versions before v3.7.4 contain a path traversal vulnerability in the getUniqueFilename endpoint that allows anonymous readers to probe filesystem existence without validation or confinement. Attackers can supply arbitrary absolute paths to determine whether files and directories exist on the host, enabling reconnaissance of the filesystem layout and installed software.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (23.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-73605: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73605?
CVE-2026-73605 is a medium-severity vulnerability in Siyuan-Note Siyuan, classified under Missing Authorization. CVSS score: 5.8/10. Published 2026-08-13.
How severe is CVE-2026-73605?
Medium severity. CVSS v3 base score is 5.8 out of 10.