Title

The TSIG keys used with the BIND 9.x implementation must be group owned by a privileged account. (Cat II impact)

Discussion

Incorrect ownership of a TSIG key file could allow an adversary to modify the file, thus defeating the security objective.

Check Content

With the assistance of the DNS Administrator, identify all of the TSIG keys used by the BIND 9.x implementation. Identify the account that the "named" process is running as: # ps -ef | grep named named 3015 1 0 12:59 ? 00:00:00 /usr/sbin/named -u named -t /var/named/chroot With the assistance of the DNS Administrator, determine the location of the TSIG keys used by the BIND 9.x implementation. # ls –al <TSIG_Key_Location> -rw-------. 1 named named 76 May 10 20:35 tsig-example.key If any of the TSIG keys are not group owned by the above account, this is a finding.

Fix Text

Change the group ownership of the TSIG keys to the named process group. # chgrp <named_proccess_group> <TSIG_key_file>

Additional Identifiers

Rule ID: SV-207564r879613_rule

Vulnerability ID: V-207564

Group Title: SRG-APP-000176-DNS-000018

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.