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.
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.004 (35.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 35.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002
Affected products
- B3log Siyuan
- Siyuan-Note Siyuan — versions < 3.6.4
Weakness classification (CWE)
References
- github.com/siyuan-note/siyuan/security/advisories/GHSA-vw86-c94w-v3x4 (Third Party Advisory)
- github.com/siyuan-note/siyuan/releases/tag/v3.6.4 (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.