Path Traversal Vulnerability in SiYuan by SiYuan Note

CVE-2026-100636

What is CVE-2026-100636?

The vulnerability in SiYuan before version 3.8.4 arises from improper validation of user-supplied folder parameters in the exportBrowserHTML endpoint. This allows authenticated administrators to execute directory traversal attacks, leading to the possibility of overwriting the index.html file in locations outside the designated workspace directory. By exploiting this flaw, attackers can introduce arbitrary HTML content, resulting in potential stored XSS attacks or defacement of the workspace.

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