CVE-2026-100635

published 2026-09-26

CVE-2026-100635: SiYuan before v3.8.4 contains an authentication bypass vulnerability in the publish service where session cookies are issued without Secure or SameSite…

Priority P3 36 medium 5.9 CVSS 3.1

AV N AC H PR N UI N S U C H I N A N

SiYuan before v3.8.4 contains an authentication bypass vulnerability in the publish service where session cookies are issued without Secure or SameSite attributes over plaintext HTTP connections. An on-path attacker can observe a valid publish-visitor-session-id cookie from a Basic Auth exchange and replay it to access authenticated publish endpoints without knowing the account password.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
siyuan-note	siyuan	< 3.8.4	3.8.4

CVSS provenance

nvd v3.1 5.9 MEDIUM CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd v4.0 8.2 HIGH CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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CWE-319