{"id":"CVE-2026-53515","aliases":["GHSA-gv74-j8m3-fg5f"],"url":"https://o3.security/vulnerability/CVE-2026-53515","summary":"Better Auth: Privilege escalation via SSO provider registration: missing admin role check in @better-auth/sso","details":"Better Auth is an authentication and authorization library for TypeScript. From 1.2.10 until 1.6.11, the @better-auth/sso plugin's POST /sso/register endpoint lets any organization member attach a new SSO provider to that organization because registerSSOProvider checks only for a membership row and does not require an owner or admin role, allowing attacker-controlled OIDC or SAML providers to drive /sso/callback/{providerId} organization provisioning. This issue is fixed in version 1.6.11.","published":"2026-07-15T17:27:00.291Z","modified":"2026-08-12T03:51:22.507111770Z","cvss":{"score":7.1,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N"},"epss":{"score":0.00238,"percentile":0.14899,"asOf":"2026-08-10"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@better-auth/sso","fixedVersion":"1.6.11"}],"fix":{"url":"https://github.com/better-auth/better-auth/commit/86765f1597378f5c3deed1b80ca91faac0a6bf00","label":"better-auth/better-auth@86765f1"},"references":[{"type":"WEB","url":"https://github.com/better-auth/better-auth/releases/tag/v1.6.11"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53515.json"},{"type":"ADVISORY","url":"https://github.com/better-auth/better-auth/security/advisories/GHSA-gv74-j8m3-fg5f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53515"},{"type":"FIX","url":"https://github.com/better-auth/better-auth/commit/86765f1597378f5c3deed1b80ca91faac0a6bf00"},{"type":"FIX","url":"https://github.com/better-auth/better-auth/pull/9220"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:22.507111770Z"}}