CVSS 3.1
7.1 highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:NCVE-2026-53515
High (7.1) in better-auth. EPSS 0.4% chance of exploitation in the next 30 days. Fixed in @better-auth/sso 1.6.11.
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.
Severity
- EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-269, CWE-285, CWE-863
- Published
- Modified
- Record from
- the NVD, synced
Affected
- better-auth:better-auth\/sso
- better-auth:better_auth
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-gv74-j8m3-fg5f | npm | @better-auth/sso | >=1.2.10 <1.6.11 | 1.6.11 |