Adam-P

**Name of the Vulnerable Software and Affected Versions** Nextcloud Server versions prior to 26.0.9 and 27.1.4 Nextcloud Enterprise Server versions prior to 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 **Description** The issue is related to the lack of restrictions on authentication attempts, allowing a remote attacker to bypass the authentication process. When a (reverse) proxy is configured as a trusted proxy, the server can be tricked into reading the wrong remote address for an attacker, enabling them to execute authentication attempts. **Recommendations** For Nextcloud Server versions prior to 26.0.9, update to version 26.0.9 or later. For Nextcloud Server versions prior to 27.1.4, update to version 27.1.4 or later. For Nextcloud Enterprise Server versions prior to 23.0.12.13, update to version 23.0.12.13 or later. For Nextcloud Enterprise Server versions prior to 24.0.12.9, update to version 24.0.12.9 or later. For Nextcloud Enterprise Server versions prior to 25.0.13.4, update to version 25.0.13.4 or later. For Nextcloud Enterprise Server versions prior to 26.0.9, update to version 26.0.9 or later. For Nextcloud Enterprise Server versions prior to 27.1.4, update to version 27.1.4 or later.