CVE-2026-25992 Details

A file read interface case bypass vulnerability has been identified in SiYuan personal knowledge management system versions 3.5.4 and prior to 3.5.5. The vulnerability exists in the '/api/file/getFile' endpoint, which employs case-sensitive string equality checks to restrict access to sensitive files. On case-insensitive file systems like Windows, attackers can exploit this by using mixed-case paths to bypass these restrictions and access protected configuration files. The issue arises because path comparisons are strictly case-sensitive, lacking case normalization or validation against identical files.

Users can update to SiYuan version 3.5.5, which addresses this vulnerability by implementing case normalization in path comparisons and applying blacklist validation on sensitive paths after normalization.