CVE-2023-39953 MEDIUM

CVE-2023-39953: Issuer not verified from obtained token in user_oidc

Vendor Nextcloud
Product security-advisories
Weakness CWE-303
Published August 10, 2023
Last update October 3, 2024

CVSS base score

4.8/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

August 10, 2023 CVE published
October 3, 2024 Record updated