CVE-2026-126265
HIGH
NVD
CVSS Score
7.4
Severity
HIGH
Published
Nov 13, 2026
Vendor
unknown
Description
SiYuan 2.1.0 before 3.8.9 contains a flaw where the loginAuth CAPTCHA challenge lives in a signed client-side cookie, allowing reuse of a solved challenge. Attackers can replay the original signed siyuan cookie with distinct wrong access codes to brute-force the code and gain an administrator session.