Checking for DNS Poisoning Vulnerability
Just a quick way to test and see if your DNS servers are vulnerable to the latest DNS Cache Poisoning vulnerability (CVE-2008-1447).
From: https://www.dns-oarc.net/oarc/services/porttest
$ dig @4.2.2.3 +short porttest.dns-oarc.net TXT
Replacing 4.2.2.3 with the IP address of your DNS server(s).