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        "dateReserved": "2026-08-11T19:56:20.006Z",
        "datePublished": "2026-09-08T13:15:50.743Z",
        "dateUpdated": "2026-10-01T15:20:31.394Z"
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            "title": "XenForo < 2.3.13 Authentication Bypass via OAuth2 Token Endpoint",
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                    "value": "XenForo before 2.3.13 contains an authentication bypass vulnerability in the OAuth2 token endpoint that allows unauthenticated attackers to obtain valid token pairs by submitting empty values for client_secret and code_verifier parameters. Attackers can exploit PHP truthy evaluation logic, which treats empty strings as false and skips client secret validation and PKCE code verifier validation, to exchange a valid authorization code for a token pair without proving client identity or holding the PKCE commitment."
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