RHEL-08-020012 - RHEL 8 must automatically lock an account when three unsuccessful logon attempts occur during a 15-minute time period.

Information

By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-force attacks, is reduced. Limits are imposed by locking the account.

RHEL 8 can utilize the "pam_faillock.so" for this purpose. Note that manual changes to the listed files may be overwritten by the "authselect" program.

From "Pam_Faillock" man pages: Note that the default directory that "pam_faillock" uses is usually cleared on system boot so the access will be reenabled after system reboot. If that is undesirable a different tally directory must be set with the "dir" option.

Satisfies: SRG-OS-000021-GPOS-00005, SRG-OS-000329-GPOS-00128

Solution

Configure the operating system to lock an account when three unsuccessful logon attempts occur in 15 minutes.

Add/Modify the appropriate sections of the "/etc/pam.d/system-auth" and "/etc/pam.d/password-auth" files to match the following lines:

auth required pam_faillock.so preauth dir=/var/log/faillock silent audit deny=3 even_deny_root fail_interval=900 unlock_time=0
auth required pam_faillock.so authfail dir=/var/log/faillock unlock_time=0
account required pam_faillock.so

The "sssd" service must be restarted for the changes to take effect. To restart the "sssd" service, run the following command:

$ sudo systemctl restart sssd.service

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_RHEL_8_V2R3_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-7a., CAT|II, CCI|CCI-000044, Rule-ID|SV-230334r1017146_rule, STIG-ID|RHEL-08-020012, Vuln-ID|V-230334

Plugin: Unix

Control ID: 0b899bc749c0eb01f058b1a036282638ad78e2e5e513328160f23a57b1dda4ce