Ensure an Administrator Account Cannot Login to Another User's Active and Locked Session

HighLevel 1Automatedmacos

Description

macOS has a privilege that can be granted to any user that will allow that user to unlock active users' sessions. Note: For organizations that are using Platform Single-Sign-On (PSSO), this setting can cause issues with syncing with your PSSO. See the note in the audit to verify if you are using PSSO. Audit: Organisations using Platform SSO (app-sso platform -s shows a configuration) should not apply this change.

How it is checked

Audit method: Shell command

shell

out=$(/usr/bin/security authorizationdb read system.login.screensaver 2>&1) || exit 1
printf '%s\n' "$out" | /usr/bin/awk -F "[<>]" '$3=="authenticate-session-owner" { ++x } END { print x+0 }'

Expected output: 1

How it is fixed

Fix method: Guidance or infrastructure patch

Terminal: sudo /usr/bin/security authorizationdb write system.login.screensaver authenticate-session-owner ; sudo /usr/bin/defaults write /Library/Preferences/com.apple.loginwindow screenUnlockMode -int 1.

Properties

Operating systems: macos-26
Tags: macossystem-access
Reference: CIS Apple macOS 26 Tahoe Benchmark v1.1.0 - 5.7 Ensure an Administrator Account Cannot Login to Another User's Active and Locked Session

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target macos