CVE-2026-100635 (GCVE-0-2026-100635)
Vulnerability from cvelistv5
Published
2026-09-26 13:23
Modified
2026-10-27 01:30
Severity ?
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
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-319 - Cleartext Transmission of Sensitive Information
Summary
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.
References
Impacted products
Vendor Product Version
siyuan-note siyuan Version: 0   ≤
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