CVE-2026-45284: Nextcloud User Oidc

High severity, CVSS 8.8. EPSS: 0.4% chance of exploitation in the next 30 days.

Nextcloud is an open source content collaboration platform. From version 1.3.6 to before version 8.4.0, an improper check allowed users that where provided by LDAP to still authenticate towards user OIDC after they where deleted. This issue has been patched in version 8.4.0.

Affected products

• Nextcloud User Oidc: from 1.3.6, before 8.4.0 (fixed in 8.4.0)

Published 2026-06-01. Last modified 2026-07-22.