Nextcloud Deck Privilege Escalation via Permission Logic bug (cve-2025-66557)
CVE-2025-66557 Published on December 5, 2025
Nextcloud Deck app allowed user with "Can share" permission to modify permissions of other non-owners
Nextcloud Deck is a kanban style organization tool aimed at personal planning and project organization for teams integrated with Nextcloud. Prior to 1.14.6 and 1.15.2, a bug in the permission logic allowed users with "Can share" permission to modify the permissions of other recipients. This vulnerability is fixed in 1.14.6 and 1.15.2.
Vulnerability Analysis
CVE-2025-66557 can be exploited with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity and availability.
Weakness Type
What is an Authorization Vulnerability?
The software does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
CVE-2025-66557 has been classified to as an Authorization vulnerability or weakness.
Products Associated with CVE-2025-66557
Want to know whenever a new CVE is published for Nextcloud Deck? stack.watch will email you.
Affected Versions
nextcloud security-advisories:- Version >= 1.15.0-beta.1, < 1.15.2 is affected.
- Version < 1.14.6 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.