Ubuntu gnome-control-center SSH Remote Login Status Misrepresentation Vulnerability

A vulnerability exists in the gnome-control-center package on Ubuntu systems that use systemd socket activation for OpenSSH. The control center fails to accurately reflect the status of SSH remote login, which can lead to unintended exposure of the local machine to remote SSH access. This issue arises because the control center relies on the status of the ssh.service, which is not active by default when socket activation is used. As a result, users may believe that remote SSH access is disabled when it is actually enabled.

Impact

This vulnerability could allow unauthorized remote access to the user's machine via SSH, contrary to the user's expectation that such access is disabled.

Reproduction

To reproduce this vulnerability, first ensure that the system is running Ubuntu 22.10 or later, where OpenSSH socket activation is the default. Then, open the GNOME control center and navigate to the Sharing tab. The SSH remote login status will incorrectly indicate that SSH access is disabled. Despite this, SSH access will be active, allowing remote connections.

Remediation

Users can update to the latest version of the gnome-control-center package to address this vulnerability. Instructions for updating can be found on the Ubuntu Security Notices page.