Vulnerability · Published Sep 26, 2026 · Assigned by VulnCheck
CVE-2026-100637SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID
High 7.6
In plain English
A high-severity security flaw in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 46% of all known vulnerabilities).
Severity (CVSS 3.1)7.6High
Exploit odds (30 days)0.6%top 53.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| siyuan-note | siyuan | 0 – before 3.8.4 |
Weakness: CWE-73 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L
References
- GitHub Security Advisory (GHSA-jhmh-hr4g-c5g2) vendor-advisory
- VulnCheck Advisory: SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID third-party-advisory