CVE-2026-100637 PUBLISHED

SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID

Assigner: VulnCheck
Reserved: 26.09.2026 Published: 26.09.2026 Updated: 26.09.2026

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.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L
CVSS Score: 8.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	High
Attack Requirements	None	Availability	Low	Availability	Low
Privileges Required	High
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L
CVSS Score: 7.6

Attack Vector	Network	Scope	Changed
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	High	Integrity Impact	High
User Interaction	None	Availability Impact	Low

CVSS 3.1

Product Status

Vendor	siyuan-note
Product	siyuan
Versions	Default: unaffected affected from 0 to 3.8.4 (excl.) Version 3.8.4 is unaffected

CVE-2026-100637 PUBLISHED

SiYuan before v3.8.4 Path Traversal via checkoutRepo sessionID

Metrics

Product Status

Credits

References

Problem Types