The flaw lets a user that can invoke the desktop publish service copy any locally readable file referenced by a file:// link in pasted HTML into the workspace assets directory without path validation, and subsequently read that file via the exposed asset URL. This results in unauthorized disclosure of sensitive data that may include credentials, configuration files, or other confidential information.

SiYuan, the personal knowledge‑management system, desktop edition, is affected in versions 3.6.0 and earlier. The vulnerability is triggered when the /api/lute/html2BlockDOM endpoint processes pasted HTML containing file:// links, and the GET /assets/* path is then used to retrieve the copied file. The issue was fixed in release 3.6.1 and later.

The CVSS score of 9.9 places the vulnerability in the critical range, while the EPSS score below 1% indicates a current low probability of exploitation. The weakness is not listed in CISA’s KEV catalog. An attacker must be able to send a request to the publish service, which generally requires at least an authenticated user role. Once this requirement is met, the attacker can read any file that the SiYuan process can read, leading to significant confidentiality loss without additional privilege escalation.