Authorization Bypass

@better-auth/stripe is vulnerable to Authorization Bypass. The vulnerability is due to inconsistent organization ID validation between the middleware and request handler, allowing authenticated users to perform unauthorized subscription actions and access billing information for other organizatio...

CVE-2025-71399

Better Auth relies on better-call, which uses the rou3 router library. In affected versions of rou3, paths are normalized by removing empty segments, so /path, //path, and ///path resolve to the same route. In Better Auth versions prior to 1.4.5 which bundles the fixed rou3, this can allow...

CVE-2025-71401

better-auth npm before 1.4.2 allows an external request to configure baseURL when it is not otherwise defined e.g., BETTERAUTHURL is unset. An attacker able to make the very first request to the server after startup can poison the router's base path, causing all routes to return 404 for all users...

CVE-2025-71401 better-auth before 1.4.2 basePath Modification DoS

better-auth npm before 1.4.2 allows an external request to configure baseURL when it is not otherwise defined e.g., BETTERAUTHURL is unset. An attacker able to make the very first request to the server after startup can poison the router's base path, causing all routes to return 404 for all users...

CVE-2025-71401

The connected CVE entry describes a vulnerability in better-auth (npm) before 1.4.2 where an external request can configure baseURL when it is not defined (e.g., BETTER_AUTH_URL unset). An attacker who can trigger the first request after startup can poison the router’s base path, causing all rout...

EUVD-2025-210592

better-auth npm before 1.4.2 allows an external request to configure baseURL when it is not otherwise defined e.g., BETTERAUTHURL is unset. An attacker able to make the very first request to the server after startup can poison the router's base path, causing all routes to return 404 for all users...

CVE-2025-71401 better-auth before 1.4.2 basePath Modification DoS

better-auth npm before 1.4.2 allows an external request to configure baseURL when it is not otherwise defined e.g., BETTERAUTHURL is unset. An attacker able to make the very first request to the server after startup can poison the router's base path, causing all routes to return 404 for all users...

CVE-2025-71400 better-auth passkey before 1.4.0 IDOR via delete-passkey

better-auth passkey versions before 1.4.0 contain an insecure direct object reference vulnerability in the passkey deletion endpoint that allows authenticated users to delete arbitrary passkeys by ID. Attackers with valid sessions can submit crafted requests to the delete-passkey endpoint with...

CVE-2025-71399

CVE-2025-71399 affects Better Auth prior to version 1.4.5, which ships a vulnerable rou3 router. In rou3, path normalization removes empty segments, causing /path, //path, and ///path to resolve to the same route. This enables an attacker to bypass disabledPaths configuration and path-based rate ...

EUVD-2025-210591

better-auth passkey versions before 1.4.0 contain an insecure direct object reference vulnerability in the passkey deletion endpoint that allows authenticated users to delete arbitrary passkeys by ID. Attackers with valid sessions can submit crafted requests to the delete-passkey endpoint with...

EUVD-2025-210590

Better Auth relies on better-call, which uses the rou3 router library. In affected versions of rou3, paths are normalized by removing empty segments, so /path, //path, and ///path resolve to the same route. In Better Auth versions prior to 1.4.5 which bundles the fixed rou3, this can allow...

CVE-2025-71399 Better Auth before 1.4.5 Path Normalization Bypass via rou3

Better Auth relies on better-call, which uses the rou3 router library. In affected versions of rou3, paths are normalized by removing empty segments, so /path, //path, and ///path resolve to the same route. In Better Auth versions prior to 1.4.5 which bundles the fixed rou3, this can allow...

CVE-2026-67333

better-auth before 1.6.13 and pre-release builds 1.7.0-beta.0 through 1.7.0-beta.3 fail to validate the scheme of redirecturis registered via the deprecated oidc-provider plugin and the mcp plugin which wraps the same provider. An attacker can register an OAuth client with a javascript:...

CVE-2026-67335

better-auth versions before 1.6.2 fail to validate the OAuth state parameter against the stored nonce when using cookie-backed state storage without PKCE. Attackers can forge the state parameter and supply an attacker-controlled authorization code to create authenticated sessions bound to the...

CVE-2025-71403

better-auth versions before 1.1.20 contain a bypass vulnerability in trustedOrigins validation logic affecting absolute URLs and wildcard domains. Attackers can construct malicious callbackURL parameters that pass origin checks and trigger open redirects to steal sensitive tokens for account...

CVE-2025-71402

better-auth versions greater than 1.3.34 and before 1.4.0 contain a vulnerability in the multi-session plugin's /sign-out after-hook, which trusts raw multi-session cookies and forwards extracted values to internalAdapter.deleteSessions without verifying the cookie signature e.g., via...

CVE-2025-71403

better-auth versions before 1.1.20 contain a bypass vulnerability in trustedOrigins validation logic affecting absolute URLs and wildcard domains. Attackers can construct malicious callbackURL parameters that pass origin checks and trigger open redirects to steal sensitive tokens for account...

CVE-2026-67334

better-auth versions before 1.6.11 fail to delete cached sessions when removing users via admin, anonymous, or SCIM endpoints when secondaryStorage is configured and storeSessionInDatabase is false. Attackers can reuse deleted user session tokens to maintain authentication for up to seven days...

CVE-2026-67333 better-auth before 1.6.13 Stored XSS via javascript redirect_uri

better-auth before 1.6.13 and pre-release builds 1.7.0-beta.0 through 1.7.0-beta.3 fail to validate the scheme of redirecturis registered via the deprecated oidc-provider plugin and the mcp plugin which wraps the same provider. An attacker can register an OAuth client with a javascript:...

CVE-2026-67334 better-auth Stale Sessions Persist After User Deletion

better-auth versions before 1.6.11 fail to delete cached sessions when removing users via admin, anonymous, or SCIM endpoints when secondaryStorage is configured and storeSessionInDatabase is false. Attackers can reuse deleted user session tokens to maintain authentication for up to seven days...