cyberstrikeus CIS 6.1 — Hide BIND Version String
Profile Applicability
- Level 1 - Authoritative Name Server
- Level 1 - Caching Only Name Server
Description
BIND includes a built-in zone, version.bind which may be queried to get the version of the name server. The version may be set to a value of none, to disable reporting of the version information.
Rationale
Making detailed BIND version information easy to obtain remotely helps attackers automate and target their attacks. The information is not necessary for the health of the server, and should not be disclosed.
Impact
None noted.
Audit Procedure
Use the dig command shown below to query the chaos class TXT record on version.bind. If there is no output from the command, or if a value of No Info or None is returned then the configuration is compliant.
$ dig @ns1.cisecurity.org version.bind chaos txt | grep '^version.bind.' | grep TXT
version.bind. 0 CH TXT "No Info"
$ dig @ns2.cisecurity.org version.bind chaos txt | grep '^version.bind.' | grep TXT
$
Remediation
Add or modify the version option to have a value of none in the BIND global options, as shown below.
options {
version none;
. . .
}
Default Value
Default value returns the current BIND detailed version.
References
None listed.
CIS Controls
| Controls Version | Control | IG 1 | IG 2 | IG 3 |
|---|---|---|---|---|
| v6 | 9 - Limitation and Control of Network Ports, Protocols, and Services | Y | Y | Y |
MITRE ATT&CK Mappings
| Tactic | Technique |
|---|---|
| Reconnaissance | T1592 - Gather Victim Host Information |
| Reconnaissance | T1592.002 - Software |
Profile
- Level 1 - Authoritative Name Server
- Level 1 - Caching Only Name Server