Vulnerability in B3log Siyuan
CVE-2026-40318
SiYuan is an open-source personal knowledge management system. In versions 3.6.3 and prior, the /api/av/removeUnusedAttributeView endpoint constructs a filesystem path using the user-controlled id parameter without validation or path boundary enforcement. An attacker can inject path traversal sequences such as ../ into the id value to escape the intended directory and delete arbitrary .json files on the server, including global configuration files and workspace metadata. This issue has been fixed in version 3.6.4.
EPSS: 0.003 (21.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H.
Affected products
- B3log Siyuan
- Siyuan-note Siyuan — versions < 3.6.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (x_refsource_MISC, Release Notes)
Frequently asked questions
- What is CVE-2026-40318?
- CVE-2026-40318 is a high-severity vulnerability in B3log Siyuan, classified under CWE-24. CVSS score: 8.5/10. Published 2026-04-16.
- How severe is CVE-2026-40318?
- High severity. CVSS v3 base score is 8.5 out of 10.