The Photon operating system must enforce the limit of three consecutive invalid logon attempts by a user during a 15-minute time period.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-258802	SRG-OS-000021-GPOS-00005	PHTN-40-000004	SV-258802r958388_rule	2024-07-11	2

Description
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.

ℹ️ Check
At the command line, run the following commands to verify accounts are locked after three consecutive invalid logon attempts by a user during a 15-minute time period: # grep '^deny =' /etc/security/faillock.conf Example result: deny = 3 If the "deny" option is not set to "3" or less (but not "0"), is missing or commented out, this is a finding. # grep '^fail_interval =' /etc/security/faillock.conf Example result: fail_interval = 900 If the "fail_interval" option is not set to "900" or more, is missing or commented out, this is a finding. Note: If faillock.conf is not used to configure the "pam_faillock.so" module, then these options may be specified on the faillock lines in the system-auth and system-account PAM files.

ℹ️ Check

At the command line, run the following commands to verify accounts are locked after three consecutive invalid logon attempts by a user during a 15-minute time period: # grep '^deny =' /etc/security/faillock.conf Example result: deny = 3 If the "deny" option is not set to "3" or less (but not "0"), is missing or commented out, this is a finding. # grep '^fail_interval =' /etc/security/faillock.conf Example result: fail_interval = 900 If the "fail_interval" option is not set to "900" or more, is missing or commented out, this is a finding. Note: If faillock.conf is not used to configure the "pam_faillock.so" module, then these options may be specified on the faillock lines in the system-auth and system-account PAM files.

✔️ Fix
Navigate to and open: /etc/security/faillock.conf Add or update the following lines: deny = 3 fail_interval = 900 Note: On vCenter appliances, the equivalent file must be edited under "/etc/applmgmt/appliance", if one exists, for the changes to persist after a reboot.