{"affected":[{"defaultStatus":"unaffected","ecosystem":"golang","packageName":"github.com/siyuan-note/siyuan/kernel","product":"siyuan","source":"CNA: VulnCheck","vendor":"siyuan-note","versions":[{"lessThan":"3.8.9","status":"affected","version":"2.1.0","versionType":"semver"},{"status":"unaffected","version":"3.8.9","versionType":"semver"}]}],"cveId":"CVE-2026-126265","cwes":["CWE-307"],"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.","epss":null,"exploits":[],"kev":null,"metrics":[{"score":9.1,"severity":"critical","source":"CNA: VulnCheck","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"},{"score":7.4,"severity":"high","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},{"score":9.1,"severity":"critical","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/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","version":"4.0"},{"score":7.4,"severity":"high","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}],"modifiedAt":1794565049133,"publishedAt":1794562610432,"references":[{"source":"CNA: VulnCheck","tags":["vendor-advisory"],"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-23g4-vqq8-5764"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/siyuan-2.1.0-before-3.8.9-captcha-bypass-via-stale-login-cookie"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-23g4-vqq8-5764"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/siyuan-2.1.0-before-3.8.9-captcha-bypass-via-stale-login-cookie"}],"remediation":[],"revision":"59e52bb176ce9a36453b18e0b0ec327e3902ede8a90bd416f8616af6ad4b3480","sources":[{"modifiedAt":1794562610432,"name":"CNA: VulnCheck","retrievedAt":1794564544822,"url":"https://www.cve.org/CVERecord?id=CVE-2026-126265"},{"modifiedAt":1794565049133,"name":"NVD","retrievedAt":1794572166006,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126265"}],"ssvc":null,"status":"published","title":"SiYuan 2.1.0 before 3.8.9 CAPTCHA Bypass via Stale Login Cookie","updatedAt":1794572166006}