CVE-2023-39953: 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…

PriorityP423medium4.8CVSS 3.1

AVNACHPRNUINSUCLILAN

EPSS

0.45%

35.6th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
nextcloud	security-advisories	—	—
nextcloud	user_oidc	>= 1.0.0 < 1.3.3	1.3.3

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