Affected: Microsoft Exchange Server, Microsoft Outlook, Microsoft Office, Microsoft Lync, Microsoft Lync Basic, Microsoft Outlook for Android, Microsoft Skype for Business, Microsoft Skype for Business Basic, Microsoft Office 365 ProPlus, Microsoft Exchange Server 2016 and 4 more

An information disclosure vulnerability exists when Exchange allows creation of entities with Display Names having non-printable characters. An authenticated attacker could exploit this vulnerability by creating entities with invalid display names, which, when added to conversations, remain invisible. This security update addresses the issue by validating display names upon creation in Microsoft Exchange, and by rendering invalid display names correctly in Microsoft Outlook clients., aka 'Microsoft Exchange Information Disclosure Vulnerability'.