Path Traversal in Siyuan-Note Siyuan
CVE-2026-74798
SiYuan kernel before v3.7.4 contains a path traversal vulnerability in the database_clean MCP tool. The tool performs only an empty-string check on the id parameter before passing it to RemoveUnusedAttributeView (kernel/model/attribute_view.go), which builds a filesystem path via filepath.Join without validating that id matches SiYuan's node-ID format. An authenticated MCP client can supply path traversal sequences in id to cause the kernel to copy an arbitrary file readable by the process into SiYuan's history directory (arbitrary file read) and then delete the original file (arbitrary file deletion). The corresponding HTTP API handler was hardened in GHSA-7hm9-v7vf-7g4w, but this MCP caller was not.
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
- Siyuan-Note Siyuan — versions 0, 3.7.4
Weakness classification (CWE)
References
- github.com/siyuan-note/siyuan/security/advisories/GHSA-43jx-gxq4-jpjc (vendor-advisory)
- www.vulncheck.com/advisories/siyuan-kernel-path-traversal-via-database-clean-mc… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-74798?
- CVE-2026-74798 is a high-severity vulnerability in Siyuan-Note Siyuan, classified under Path Traversal. CVSS score: 8.7/10. Published 2026-08-17.
- How severe is CVE-2026-74798?
- High severity. CVSS v3 base score is 8.7 out of 10.