The Photon operating system must prevent leaking information of the existence of a user account.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-258859	SRG-OS-000021-GPOS-00005	PHTN-40-000193	SV-258859r958388_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. If the pam_faillock.so module is not configured to use the silent flag it could leak information about the existence or nonexistence of a user account.

ℹ️ Check
At the command line, run the following command to verify account information is not leaked during the login process: # grep '^silent' /etc/security/faillock.conf Example result: silent If the "silent" option is not set, is missing or commented out, this is a finding. Note: If faillock.conf is not used to configure pam_faillock.so then these options may be specified on the faillock lines in the system-auth and system-account files.

ℹ️ Check

At the command line, run the following command to verify account information is not leaked during the login process: # grep '^silent' /etc/security/faillock.conf Example result: silent If the "silent" option is not set, is missing or commented out, this is a finding. Note: If faillock.conf is not used to configure pam_faillock.so then these options may be specified on the faillock lines in the system-auth and system-account files.

✔️ Fix
Navigate to and open: /etc/security/faillock.conf Add or update the following lines: silent 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.