CVE-2025-48951: Auth0-PHP SDK Deserialization of Untrusted Data vulnerability

Overview The Auth0 PHP SDK contains a vulnerability due to insecure deserialization of cookie data. If exploited, since SDKs process cookie content without prior authentication, a threat actor could send a specially crafted cookie containing malicious serialized data.

Am I Affected? You are affected by this vulnerability if you meet the following preconditions:

  1. Applications using the Auth0-PHP SDK, versions between 8.0.0-BETA3 to 8.3.0.
  2. Applications using the following SDKs that rely on the Auth0-PHP SDK versions between 8.0.0-BETA3 to 8.3.0: a. Auth0/symfony, b. Auth0/laravel-auth0, c. Auth0/wordpress.

Fix Upgrade Auth0/Auth0-PHP to 8.3.1.

Acknowledgement Okta would like to thank Andreas Forsblom for discovering this vulnerability.

References

Code Behaviors & Features

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