Path Traversal Vulnerability in SiYuan by SiYuan Note
CVE-2026-100637

8.3HIGH

Key Information:

Vendor

Siyuan-note

Status
Siyuan
Vendor
CVE Published:
26 September 2026

What is CVE-2026-100637?

Versions of SiYuan prior to v3.8.4 are vulnerable to a path traversal issue through the checkoutRepo endpoint. This vulnerability permits authenticated administrators to manipulate the sessionID parameter, potentially allowing them to write JSON files outside designated workspace directories. By employing directory traversal sequences, attackers could overwrite existing JSON files within kernel-writable directories, leading to unauthorized access or data manipulation.

Affected Version(s)

siyuan 0 < 3.8.4

siyuan 3.8.4

References

https://github.com/siyuan-note/siyuan/security/advisories...
vendor-advisory
https://www.vulncheck.com/advisories/siyuan-before-3.8.4-...
third-party-advisory

CVSS V4

Score:
8.3
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

manus-use
.