cis-bind9-v301-8-3

name	cis-bind9-v301-8-3
description	Configure a Logging Syslog Channel (Scored)
category	cis-bind
version	3.0.1
author	cyberstrike-official
tags	["cis","bind","dns","isc-bind","bind9","operations","logging"]
cis_id	8.3
cis_benchmark	CIS ISC BIND DNS Server 9.9 Benchmark v3.0.1
tech_stack	["bind","isc-bind","dns","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS 8.3 — Configure a Logging Syslog Channel

Profile Applicability

• Level 1 - Authoritative Name Server
• Level 1 - Caching Only Name Server

Description

The syslog option of the logging configuration allows specification of the syslog facility to send log events. A syslog channel should be configured with the value of daemon or other appropriate syslog facility. The default and general categories should be included and the severity level should be info or lower.

Rationale

Configuring a syslog channel allows BIND to log important information via the standard system syslog facility. It is important that the BIND logs be included with the system monitoring and response that is performed on other system logs, and the syslog facility is helpful to ensure that the important log information isn't lost, or ignored.

Impact

None noted.

Audit Procedure

Search the configuration file for a syslog logging channel, as shown below.

# grep -C 3 channel /etc/named.conf | egrep '^\s+syslog\s+'
            syslog daemon;        # send to syslog's daemon facility

Usage of the syslog facility daemon is common practice, but other facilities may be configured.

Remediation

Configure a syslog channel to capture at least the default and general categories of log events. For external authoritative name servers, the category lame-servers may be redirect to null, so that it is not logged. Using lame name servers is common for the domains used for SPAM and may overload the log with information that is not very useful.

logging {
. . .
      // Syslog
      channel default_syslog {
              syslog daemon;        # send to syslog's daemon facility
              severity info;        # only send priority info and higher
      };

      category default { default_syslog; };
      category general { default_syslog; };
      // Too many lame servers, especially from SPAM
      category lame-servers { null; };

Default Value

There is no syslog channel by default.

References

None listed.

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v6	6.6 - Deploy A SIEM OR Log Analysis Tools for Aggregation and Correlation/Analysis