Microsoft CVE-2019-0588: Microsoft Exchange Information Disclosure Vulnerability

An information disclosure vulnerability exists when the Microsoft Exchange PowerShell API grants calendar contributors more view permissions than intended. To exploit this vulnerability, an attacker would need to be granted contributor access to an Exchange Calendar by an administrator via PowerShell. The attacker would then be able to view additional details about the calendar that would normally be hidden.
The security update addresses the vulnerability by modifying how the Exchange PowerShell API grants permissions to contributors.