RHEL 9 must prohibit the use of cached authenticators after one day.

STIG ID: RHEL-09-631020  |  SRG: SRG-OS-000383-GPOS-00166 |  Severity: medium |  CCI: CCI-002007 |  Vulnerability Id: V-258133

Vulnerability Discussion

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Check

Verify that the System Security Services Daemon (SSSD) prohibits the use of cached authentications after one day.

Note: Cached authentication settings should be configured even if smart card authentication is not used on the system.

Check that SSSD allows cached authentications with the following command:

$ sudo grep -ir cache_credentials /etc/sssd/sssd.conf /etc/sssd/conf.d/

cache_credentials = true

If "cache_credentials" is set to "false" or missing from the configuration file, this is not a finding and no further checks are required.

If "cache_credentials" is set to "true", check that SSSD prohibits the use of cached authentications after one day with the following command:

$ sudo grep -ir offline_credentials_expiration /etc/sssd/sssd.conf /etc/sssd/conf.d/

offline_credentials_expiration = 1

If "offline_credentials_expiration" is not set to a value of "1", this is a finding.

Fix

Configure the SSSD to prohibit the use of cached authentications after one day.

Edit the file "/etc/sssd/sssd.conf" or a configuration file in "/etc/sssd/conf.d" and add or edit the following line just below the line [pam]:

offline_credentials_expiration = 1