This update fixes insecure temp file handling of the DHCP server, which could have been exploited locally by a symlink attack, and improves security of the chroot jail. The dhcp server used easily guessable filenames when creating a new lease file in the directory /var/lib/dhcp. Since the directory was owned by the nobody user, another process running under the same user id could trick the server (which initially runs as root when starting up) into overwriting arbitrary files via a symlink attack. The DHCP server now runs under its own user id (dhcpd), the leases file has been moved to /var/lib/dhcp/db, and the rest of the chroot jail is owned by root.
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center