cis-ubuntu2004-v300-6-1-2

DevOps & Security

Ensure filesystem integrity is regularly checked

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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-v300-6-1-2/SKILL.md

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6.1.2 Ensure filesystem integrity is regularly checked (Automated)

Profile

Level 1 - Server
Level 1 - Workstation

Description

Periodic checking of the filesystem integrity is needed to detect changes to the filesystem.

Rationale

Periodic file checking allows the system administrator to determine on a regular basis if critical files have been changed in an unauthorized fashion.

Audit Procedure

Command Line

Run the following command:

# systemctl list-unit-files | awk '$1~/^dailyaidecheck\.(timer|service)$/{print $1 "\t" $2}'

Example output:

dailyaidecheck.service  static
dailyaidecheck.timer    enabled

Verify dailyaidecheck.timer is enabled and dailyaidecheck.service is either static or enabled.

Run the following command to verify dailyaidecheck.timer is active:

# systemctl is-active dailyaidecheck.timer

Expected Result

active

Remediation

Command Line

Run the following command to unmask dailyaidecheck.timer and dailyaidecheck.service:

# systemctl unmask dailyaidecheck.timer dailyaidecheck.service

Run the following command to enable and start dailyaidecheck.timer:

# systemctl --now enable dailyaidecheck.timer

Default Value

Not configured by default.

References

https://github.com/konstruktoid/hardening/blob/master/config/aidecheck.service
https://github.com/konstruktoid/hardening/blob/master/config/aidecheck.timer
NIST SP 800-53 Rev. 5: AU-2

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	3.14 Log Sensitive Data Access
v7	14.9 Enforce Detail Logging for Access or Changes to Sensitive Data

MITRE ATT&CK Mappings

Techniques / Sub-techniques	Tactics	Mitigations
T1036, T1036.002, T1036.003, T1036.004, T1036.005, T1565, T1565.001	TA0040	M1022