Vulnerability Discussion

Operating system remote access functionality must have the capability to immediately disconnect current users remotely accessing the information system and/or disable further remote access. The speed of disconnect or disablement varies based on the criticality of mission functions and the need to eliminate immediate or future remote access to organizational information systems.

SUSE operating systems are capable to immediately stop remote connections and services by a local system administrator.

To immediately disconnect or disable remote access, the firewall needs to be set into panic mode.

> sudo firewall-cmd --panic-on

To enable remote connection again, panic mode needs to be disabled.

> sudo firewall-cmd --panic-off

Check

Verify "firewalld" is configured to protect the SUSE operating system.

Run the following command:

> systemctl status firewalld.service
firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: disabled)
Active: active (running) since Wed 2019-11-06 10:58:11 CET; 24h ago
Docs: man:firewalld(1)
Main PID: 1105 (firewalld)
Tasks: 2 (limit: 4915)
CGroup: /system.slice/firewalld.service
??1105 /usr/bin/python3 -Es /usr/sbin/firewalld --nofork --nopid

If the service is not enabled, this is a finding.

If the service is not active, this is a finding.

Fix

Configure the SUSE operating system to enable the firewall service. This is needed to be able to immediately disconnect or disable remote access to the whole system.

Enable the "firewalld.service" by running the following command:

> sudo systemctl enable firewalld.service

Start the "firewalld.service" by running the following command:

> sudo systemctl start firewalld.service

To immediately disconnect or disable remote access the firewall needs to be set into panic mode.

> sudo firewall-cmd --panic-on

To enable remote connection again, panic mode needs to be disabled.

> sudo firewall-cmd --panic-off