{"id":"CVE-2026-53516","state":"PUBLISHED","title":"Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email","description":"Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.11, Better Auth's OAuth callback auto-link gate in handleOAuthUserInfo accepts implicit account linking when the OAuth provider asserts email_verified: true without requiring the local user row's emailVerified field to also be true, allowing an attacker who pre-registers a victim email through /sign-up/email to bind the victim's OAuth identity to the attacker's account. The same primitive affects one-tap, and emailAndPassword.requireEmailVerification: true does not mitigate the link-time verification change. This issue is fixed in version 1.6.11.","publishedAt":"2026-07-15T17:13:16.431Z","updatedAt":"2026-07-15T17:52:35.572Z","severity":{"score":8.3,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["better-auth better-auth"],"affected":[{"vendor":"better-auth","product":"better-auth","versions":[{"version":"< 1.6.11","status":"affected"}]}],"references":["https://github.com/better-auth/better-auth/security/advisories/GHSA-g38m-r43w-p2q7","https://github.com/better-auth/better-auth/pull/9578","https://github.com/better-auth/better-auth/commit/da7e50beee849c59a2ed1ec6b3a38cc6ab9fb563","https://github.com/better-auth/better-auth/releases/tag/v1.6.11"],"weaknesses":["CWE-287","CWE-345"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53516.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53516","state":"PUBLISHED","datePublished":"2026-07-15T17:13:16.431Z","dateUpdated":"2026-07-15T17:52:35.572Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-09T17:30:33.456Z"},"containers":{"cna":{"title":"Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email","descriptions":[{"lang":"en","value":"Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.11, Better Auth's OAuth callback auto-link gate in handleOAuthUserInfo accepts implicit account linking when the OAuth provider asserts email_verified: true without requiring the local user row's emailVerified field to also be true, allowing an attacker who pre-registers a victim email through /sign-up/email to bind the victim's OAuth identity to the attacker's account. The same primitive affects one-tap, and emailAndPassword.requireEmailVerification: true does not mitigate the link-time verification change. This issue is fixed in version 1.6.11."}],"affected":[{"vendor":"better-auth","product":"better-auth","versions":[{"version":"< 1.6.11","status":"affected"}]}],"references":[{"url":"https://github.com/better-auth/better-auth/security/advisories/GHSA-g38m-r43w-p2q7","name":"https://github.com/better-auth/better-auth/security/advisories/GHSA-g38m-r43w-p2q7","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/better-auth/better-auth/pull/9578","name":"https://github.com/better-auth/better-auth/pull/9578","tags":["x_refsource_MISC"]},{"url":"https://github.com/better-auth/better-auth/commit/da7e50beee849c59a2ed1ec6b3a38cc6ab9fb563","name":"https://github.com/better-auth/better-auth/commit/da7e50beee849c59a2ed1ec6b3a38cc6ab9fb563","tags":["x_refsource_MISC"]},{"url":"https://github.com/better-auth/better-auth/releases/tag/v1.6.11","name":"https://github.com/better-auth/better-auth/releases/tag/v1.6.11","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":8.3,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-287","lang":"en","description":"CWE-287: Improper Authentication","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-345","lang":"en","description":"CWE-345: Insufficient Verification of Data Authenticity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-15T17:13:16.431Z"},"source":{"advisory":"GHSA-g38m-r43w-p2q7","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-15T17:51:30.733244Z","id":"CVE-2026-53516","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-15T17:52:35.572Z"}}]}}}