The 'Login to Disabled Account' detection rule is designed to identify unauthorized attempts to sign in to user accounts that have been disabled within Azure Active Directory (Azure AD). Specifically, it captures scenarios where a login attempt returns a ResultType of 50057, which indicates that the user account is disabled and was deactivated by an administrator. This is an important security measure as it can help prevent potential misuse of disabled accounts that should not be accessed. The rule analyzes logs from Azure's signinlogs service and flags any instances where a disabled account is targeted, thereby alerting administrators to possible attack attempts. The detection mechanism is straightforward, utilizing a selection based on specific failed login details. It is attributed a medium severity level, reflecting its importance in the context of privileged account security management. Furthermore, while the rule acknowledges the possibility of false positives, particularly through unknown causes, it plays a key role in bolstering the overall security posture by monitoring access attempts on disabled accounts in a cloud infrastructure.