cis-ubuntu2004-v300-2-3-3-2

DevOps & Security

Ensure chrony is running as user _chrony

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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-v300-2-3-3-2/SKILL.md

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Ensure chrony is running as user _chrony

Profile

Level 1 - Server
Level 1 - Workstation

Description

The chrony package is installed with a dedicated user account _chrony. This account is granted the access required by the chronyd service

Rationale

The chronyd service should run with only the required privilidges

Audit

IF - chrony is in use on the system, run the following command to verify the chronyd service is being run as the _chrony user:

Command Line

# ps -ef | awk '(/[c]hronyd/ && $1!="_chrony") { print $1 }'

Expected Result

Nothing should be returned

Remediation

Add or edit the user line to /etc/chrony/chrony.conf or a file ending in .conf in /etc/chrony/conf.d/:

Command Line

user _chrony

- OR -

If another time synchronization service is in use on the system, run the following command to remove chrony from the system:

# apt purge chrony
# apt autoremove chrony

Default Value

user _chrony

References

NIST SP 800-53 Rev. 5: AU-8

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	0.0 Explicitly Not MappedExplicitly Not Mapped
v7	0.0 Explicitly Not MappedExplicitly Not Mapped

MITRE ATT&CK Mappings

Techniques / Sub-techniques	Tactics	Mitigations
T1070, T1070.002, T1562, T1562.001	TA0002	M1022