What’s Vulnerable › Vulnerabilities

CVE-2026-100637: SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID

• Severity: high (CVSS 7.6 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-26 · updated 2026-10-05
• Weakness: CWE-73

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

• siyuan-note siyuan: before 3.8.4 — fixed in 3.8.4

How to fix

Upgrade to a fixed version: siyuan-note siyuan 3.8.4. Check the vendor advisory for mitigations.

References

• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2
• https://www.vulncheck.com/advisories/siyuan-before-3.8.4-path-traversal-via-checkoutrepo-sessionid
• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2

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