Details
Any host that can query a resolving name server has the potential to poison the servers name cache or take advantage of other vulnerabilities that may be accessed through the query service. The best way to prevent this type of attack is to limit queries to internal hosts, which need to have this service available to them.
To guard against poisoning, name servers authoritative for .mil domains should be separated functionally from name servers that resolve queries on behalf of internal clients. Organizations may achieve this separation by dedicating machines to each function or, if possible, by running two instances of the name server software on the same machine; one for the authoritative function and the other for the resolving function. In this design, each name server process may be bound to a different IP address or network interface to implement the required segregation.
NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.
Solution
Configure the caching name server to accept recursive queries only from the IP addresses and address ranges of known supported clients.
Edit the ‘named.conf’ file and add the following to the options statement:
allow-query {trustworthy_hosts;};
allow-recursion {trustworthy_hosts;};
Restart the BIND 9.x process
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: System and Communications Protection.This control applies to the following type of system Unix.
References
- 800-53|SC-5(1)
- CAT|II
- CCI|CCI-001094
- Rule-ID|SV-207560r612253_rule
- STIG-ID|BIND-9X-001080
- STIG-Legacy|SV-87049
- STIG-Legacy|V-72425
- Vuln-ID|V-207560