CVE-2026-25992: SiYuan has a File Read Interface Case Bypass Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-02-10 · updated 2026-06-17
Weakness: CWE-22

Description

SiYuan is a personal knowledge management system. Prior to 3.5.5, the /api/file/getFile endpoint uses case-sensitive string equality checks to block access to sensitive files. On case-insensitive file systems such as Windows, attackers can bypass restrictions using mixed-case paths and read protected configuration files. This vulnerability is fixed in 3.5.5.

Affected products

siyuan-note siyuan: before 3.5.5 — fixed in 3.5.5

How to fix

Upgrade to a fixed version: siyuan-note siyuan 3.5.5. Check the vendor advisory for mitigations.

References

https://github.com/siyuan-note/siyuan/releases/tag/v3.5.5
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-f72r-2h5j-7639

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