CVE-2026-45543: Nextcloud Forms

Medium severity, CVSS 5.3. EPSS: 0.5% chance of exploitation in the next 30 days.

Nextcloud is an open source content collaboration platform. From version 4.3.0 to before version 5.2.7, a removed collaborator retains unauthorized read access to uploaded respondent files for the affected form. The scope is limited to uploaded files for forms where that user previously had results access. This issue has been patched in version 5.2.7.

Affected products

• Nextcloud Forms: from 4.3.0, before 5.2.7 (fixed in 5.2.7)

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