RHEL 9 must be configured so that the cryptographic hashes of system files match vendor values.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-257823	RHEL-09-214030	SV-257823r925456_rule		Medium

Description
The hashes of important files like system executables should match the information given by the RPM database. Executables with erroneous hashes could be a sign of nefarious activity on the system.

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2023-12-01

Details

Check Text ( C-61564r925454_chk )
The following command will list which files on the system have file hashes different from what is expected by the RPM database: $ rpm -Va --noconfig \| awk '$1 ~ /..5/ && $2 != "c"' If there is output, this is a finding.

Fix Text (F-61488r925455_fix)
Given output from the check command, identify the package that provides the output and reinstall it. The following trimmed example output shows a package that has failed verification, been identified, and been reinstalled: $ rpm -Va --noconfig \| awk '$1 ~ /..5/ && $2 != "c"' S.5....T. /usr/bin/znew $ sudo dnf provides /usr/bin/znew [...] gzip-1.10-8.el9.x86_64 : The GNU data compression program [...] $ sudo dnf reinstall gzip [...] $ rpm -Va --noconfig \| awk '$1 ~ /..5/ && $2 != "c"' [no output]

Fix Text (F-61488r925455_fix)

Given output from the check command, identify the package that provides the output and reinstall it. The following trimmed example output shows a package that has failed verification, been identified, and been reinstalled:

$ rpm -Va --noconfig | awk '$1 ~ /..5/ && $2 != "c"'
S.5....T. /usr/bin/znew
$ sudo dnf provides /usr/bin/znew
[...]
gzip-1.10-8.el9.x86_64 : The GNU data compression program
[...]
$ sudo dnf reinstall gzip
[...]
$ rpm -Va --noconfig | awk '$1 ~ /..5/ && $2 != "c"'
[no output]