{"id":"CVE-2026-73309","state":"PUBLISHED","title":"XenForo < 2.3.13 Authentication Bypass via OAuth2 Token Endpoint","description":"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. 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