SB2025120514 - Improper access control in Nextcloud Deck app
Published: December 5, 2025
Security Bulletin ID
SB2025120514
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Improper access control (CVE-ID: CVE-2025-66557)
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to a bug in the permission logic. A remote user can bypass implemented security restrictions and modify the permissions of other recipients.
Remediation
Install update from vendor's website.