CVE-2025-66548: Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud.
CVE-2025-66548 · Severity: low · CVSS 3.3 · Published 2025-12-05
Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.12.7, 1.14.4, and 1.15.1, file extension can be spoofed by using RTLO characters, tricking users into download files with a different extension than what is displayed. This vulnerability is fixed in 1.12.7, 1.14.4, and 1.15.1.
No. Junglewise Threat Intelligence has no report of CVE-2025-66548 being exploited in the wild.
How severe is CVE-2025-66548?
Low severity, with a CVSS score of 3.3, published 5 December 2025.
Which products and versions are affected?
Nextcloud Deck. The advisory does not name versions.
Is there a fix for CVE-2025-66548?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2025-66548?
Check whether you run Nextcloud Deck. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.