The vulnerability resides in Siyuan’s IsSensitivePath function, which uses a denylist to prevent file access outside the workspace. An incomplete denylist allows external calls to the globalCopyFiles and importStdMd endpoints to read arbitrary files from critical Linux directories such as /opt, /usr, /home, /mnt, and /media. This can expose sensitive configuration files, binaries, or personal data, leading to a compromise of confidentiality. The weakness is a classic path traversal issue (CWE‑22).

Siyuan, a personal knowledge management system provided by siyuan-note, is affected whenever it runs a version older than 3.6.2. Versions prior to 3.6.2 lack the complete denylist and therefore allow the exploit. The advisory specifically lists version 3.6.2 as containing the correct fix.

The CVSS score of 6.8 classifies this as a medium severity issue, while the EPSS score of less than 1% indicates a currently low probability of exploitation. The vulnerability has not been added to the CISA KEV catalog, implying no known widespread exploitation. Attackers can leverage the exposed REST endpoints – a likely remote attack vector – to read sensitive files. Successful exploitation would only require network access to the endpoints or local execution of the affected code base.