CVE-2023-39953 (user_oidc)

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. No known workarounds are available.

1.0.0 access attack backend cloud cloud platform connect cve man-in-the-middle missing nextcloud oidc patch platform token verification version version 1