CVE-2023-28848: Nextcloud User Oidc

Medium severity, CVSS 5.4. EPSS: 0.3% chance of exploitation in the next 30 days.

user_oidc is the OIDC connect user backend for Nextcloud, an open source collaboration platform. A vulnerability in versions 1.0.0 until 1.3.0 effectively allowed an attacker to bypass the state protection as they could just copy the expected state token from the first request to their second request. Users should upgrade user_oidc to 1.3.0 to receive a patch for the issue. No known workarounds are available.

Affected products

• Nextcloud User Oidc: from 1.0.0, before 1.3.0 (fixed in 1.3.0)

Published 2023-04-04. Last modified 2026-06-17.