Title

The macOS system must enforce session lock no more than five seconds after screen saver is started. (Cat II impact)

Discussion

A screen saver must be enabled and the system must be configured to require a password to unlock once the screensaver has been on for a maximum of five seconds. An unattended system with an excessive grace period is vulnerable to a malicious user.

Check Content

Verify the macOS system is configured to initiate a session lock within five seconds of the screen saver starting with the following command: /usr/bin/osascript -l JavaScript << EOS function run() { let delay = ObjC.unwrap($.NSUserDefaults.alloc.initWithSuiteName('com.apple.screensaver')\ .objectForKey('askForPasswordDelay')) if ( delay <= 5 ) { return("true") } else { return("false") } } EOS If the result is not "true", this is a finding.

Fix Text

Configure the macOS system to initiate a session lock within five seconds of the screen saver starting by installing the "com.apple.screensaver" configuration profile.

Additional Identifiers

Rule ID: SV-259420r940882_rule

Vulnerability ID: V-259420

Group Title: SRG-OS-000028-GPOS-00009

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.