cis-ubuntu2004-v300-2-1-10

DevOps & Security

Ensure nis server services are not in use

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_20.04_LTS_Benchmark_v3.0.0/cis-ubuntu2004-v300-2-1-10/SKILL.md

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2.1.10 Ensure nis server services are not in use (Automated)

Profile

Level 1 - Server
Level 1 - Workstation

Description

The Network Information Service (NIS) (formally known as Yellow Pages) is a client-server directory service protocol for distributing system configuration files. The NIS server software is the ypserv package.

Rationale

The NIS service is inherently an insecure system that has been vulnerable to DOS attacks, buffer overflows and has poor authentication for querying NIS maps. NIS generally has been replaced by LDAP based authentication. It is recommended that the service be disabled and more secure services be used.

Audit Procedure

Command Line

Run the following command to verify ypserv is not installed:

# dpkg-query -W -f='${binary:Package}\t${Status}\t${db:Status-Status}\n' ypserv

If installed, run:

# systemctl is-enabled ypserv.service
# systemctl is-active ypserv.service

Verify the service is not enabled and not active.

Expected Result

ypserv should not be installed, or if installed, the service should be stopped and masked.

Remediation

Command Line

Run the following commands to stop, mask, and purge ypserv:

# systemctl stop ypserv.service
# systemctl mask ypserv.service
# apt purge ypserv

Default Value

ypserv is not installed by default.

References

NIST SP 800-53 Rev. 5: CM-7

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software		x	x
v7	9.2 Ensure Only Approved Ports, Protocols and Services Are Running		x	x

MITRE ATT&CK Mappings: T1203, T1210, T1543, T1543.002 | TA0008 | M1042