CVE-2026-30869: b3log siyuan Path Traversal

Vulnerability summary

CVE-2026-30869 is a critical (CVSS 9.8) Path Traversal vulnerability in b3log siyuan. EPSS estimates a 1.17% chance of exploitation in the next 30 days, higher than 67% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 09-03-2026
   PublishedVulnerability first disclosed.
2. 10-03-2026
   Last modifiedVulnerability information updated.

Description

SiYuan is a personal knowledge management system. Prior to 3.5.10, a path traversal vulnerability in the /export endpoint allows an attacker to read arbitrary files from the server filesystem. By exploiting double‑encoded traversal sequences, an attacker can access sensitive files such as conf/conf.json, which contains secrets including the API token, cookie signing key, and workspace access authentication code. Leaking these secrets may enable administrative access to the SiYuan kernel API, and in certain deployment scenarios could potentially be chained into remote code execution (RCE). This vulnerability is fixed in 3.5.10.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.