{"schema":"threatline.record/2","record":{"id":"CVE-2026-110863","aliases":["GHSA-mx9r-x6ww-qjw9"],"summary":"Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers","details":"Better Auth @better-auth/sso from 1.7.0-rc.2 before 1.7.3 contains an authentication bypass vulnerability that allows authenticated users to sign in as other users by registering a personal SSO provider. Attackers can copy a legitimate provider's OIDC issuer or SAML entity ID and assert a victim's subject or NameID, because account lookup ignores providerId, creating sessions for victim accounts.","categories":["Unclassified"],"product":"sso","vendor":"better-auth","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-110863","source_modified_at":"2026-10-16T17:14:33.345Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"sso","vendor":"better-auth","versions":[{"version":"1.7.0-rc.2","status":"affected","versionType":"semver","lessThan":"1.7.3"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-110863","source_modified_at":"2026-10-16T17:14:33.345Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"sso","ecosystem":null},"version":"1.7.3","basis":"first unaffected version stated in the CVE record"}],"cvss":8.6,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00269,"percentile":0.18069,"score_date":"2026-10-23"},"published_at":"2026-10-14T22:52:50.378Z","modified_at":"2026-10-16T17:14:33.345Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-110863","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-16T17:14:33.345Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-110863","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/better-auth/better-auth/security/advisories/GHSA-mx9r-x6ww-qjw9","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/better-auth-better-auth-sso-before-1.7.3-authentication-bypass-via-personal-sso-providers","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"total","assessed_at":"2026-10-16T16:35:48.861225Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-16T17:14:33.345Z","content_hash":"a105ad49dc472bc5d75a8a815290306be4bd3ba5a6bb942ba9670be658862013"}}