{"id":"CVE-2026-100635","revision":"4783737dfb844f6f9d6df76ee7874f9f","records":[{"revision":"4783737dfb844f6f9d6df76ee7874f9f","observedAt":"2026-10-27T03:22:55.977+00:00","statement":{"source":"cve-program","id":"CVE-2026-100635","aliases":[],"title":"SiYuan before v3.8.4 Authentication Bypass via Plaintext Session Cookie","description":"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.","state":0,"publishedAt":"2026-09-26T13:23:09.854+00:00","modifiedAt":"2026-10-27T01:30:29.704+00:00","affected":[{"ecosystem":"Vendor product","name":"siyuan","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"siyuan-note\",\n                    \"product\": \"siyuan\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"packageURL\": \"pkg:golang/github.com/siyuan-note/siyuan/kernel\",\n                    \"versions\": [\n                        {\n                            \"version\": \"0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\",\n                            \"lessThan\": \"3.8.4\"\n                        },\n                        {\n                            \"version\": \"3.8.4\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"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","score":8.2,"severity":"HIGH"},{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","score":5.9,"severity":"MEDIUM"}],"references":["https://github.com/siyuan-note/siyuan/security/advisories/GHSA-7j37-4gq6-wm7m","https://github.com/siyuan-note/siyuan/commit/79d47867b106467c951475a9193455b48d1f3682","https://github.com/siyuan-note/siyuan/commit/ff4d215f78a8d6e6db6052be18b5f9f4db9c7d68","https://www.vulncheck.com/advisories/siyuan-before-3.8.4-authentication-bypass-via-plaintext-session-cookie"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-100635","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-100635","identifiers":["CVE-2026-100635"]},"retained":false,"historicalAffected":[]}],"coverage":[]}