Vulnerability Discussion
Centralized cryptographic policies simplify applying secure ciphers across an operating system and the applications that run on that operating system. Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data.
Satisfies: SRG-OS-000396-GPOS-00176, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174
Check
Verify that RHEL 9 custom crypto policies are loaded correctly.
List all of the crypto backends configured on the system.
$ ls -l /etc/crypto-policies/back-ends/
lrwxrwxrwx. 1 root root 40 Oct 7 08:44 bind.config -> /usr/share/crypto-policies/FIPS/bind.txt
lrwxrwxrwx. 1 root root 42 Oct 7 08:44 gnutls.config -> /usr/share/crypto-policies/FIPS/gnutls.txt
lrwxrwxrwx. 1 root root 40 Oct 7 08:44 java.config -> /usr/share/crypto-policies/FIPS/java.txt
lrwxrwxrwx. 1 root root 46 Oct 7 08:44 javasystem.config -> /usr/share/crypto-policies/FIPS/javasystem.txt
lrwxrwxrwx. 1 root root 40 Oct 7 08:44 krb5.config -> /usr/share/crypto-policies/FIPS/krb5.txt
lrwxrwxrwx. 1 root root 45 Oct 7 08:44 libreswan.config -> /usr/share/crypto-policies/FIPS/libreswan.txt
lrwxrwxrwx. 1 root root 42 Oct 7 08:44 libssh.config -> /usr/share/crypto-policies/FIPS/libssh.txt
lrwxrwxrwx. 1 root root 39 Oct 7 08:44 nss.config -> /usr/share/crypto-policies/FIPS/nss.txt
lrwxrwxrwx. 1 root root 43 Oct 7 08:44 openssh.config -> /usr/share/crypto-policies/FIPS/openssh.txt
lrwxrwxrwx. 1 root root 49 Oct 7 08:44 opensshserver.config -> /usr/share/crypto-policies/FIPS/opensshserver.txt
lrwxrwxrwx. 1 root root 46 Oct 7 08:44 opensslcnf.config -> /usr/share/crypto-policies/FIPS/opensslcnf.txt
lrwxrwxrwx. 1 root root 43 Oct 7 08:44 openssl.config -> /usr/share/crypto-policies/FIPS/openssl.txt
If the paths do not point the respective files under /usr/share/crypto-policies/FIPS path, this is a finding.
Fix
Configure RHEL 9 to FIPS crypto policy.
$ sudo ln -s /usr/share/crypto-policies/FIPS/.txt /etc/crypto-policies/back-ends/.conf
Replace with every service that is not set to FIPS.
The system must be rebooted to make the changes to take effect.