Authentication Bypass in Better Auth OAuth Proxy Plugin by Better Auth

CVE-2026-110864

What is CVE-2026-110864?

The Better Auth OAuth Proxy plugin, present in versions before 1.7.7, is vulnerable to an authentication bypass attack. Attackers can exploit this flaw by forging encrypted profiles that allow them to impersonate other users without valid authentication credentials. This vulnerability arises when the proxy shares a global secret, enabling assailants to generate encrypted states for fake profiles using a victim's verified email. Through this method, attackers can easily gain unauthorized access to accounts by exploiting implicit linking mechanisms, posing significant risks to user data security.

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