{"api_version":"1","generated_at":"2026-07-24T23:41:15+00:00","cve":"CVE-2023-39953","urls":{"html":"https://cve.report/CVE-2023-39953","api":"https://cve.report/api/cve/CVE-2023-39953.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2023-39953","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-39953"},"summary":{"title":"CVE-2023-39953","description":"user_oidc provides the OIDC connect user backend for Nextcloud, an open-source cloud platform. Starting in version 1.0.0 and prior to version 1.3.3, missing verification of the issuer would have allowed an attacker to perform a man-in-the-middle attack returning corrupted or known token they also have access to. user_oidc 1.3.3 contains a patch. 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