Authentication Bypass Vulnerability in Ueberauth Apple Plugin

CVE-2026-55954

What is CVE-2026-55954?

The Ueberauth Apple plugin contains a security flaw that allows attackers to bypass authentication through spoofed ID tokens. Specifically, the plugin fails to validate crucial claims present in the ID token, such as iss, aud, exp, and iat. An attacker can exploit this by using an Apple-signed ID token of a victim, which could be obtained through various means such as expired token capture or sharing between sibling clients within the same Apple developer team. This vulnerability enables unauthorized access to user accounts, as tokens can remain valid indefinitely due to the lack of expiration checks. It is imperative to update to the latest version to mitigate the risks associated with this vulnerability.

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