Exchange 2019 and 2016 Security Updates for September 2019

Security updates have been released for Exchange 2016 and Exchange 2019.

  • CVE-2019-1233: Microsoft Exchange Denial of Service Vulnerability
    A denial of service vulnerability exists in Microsoft Exchange Server software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could cause a remote denial of service against a system. Exploitation of the vulnerability requires that a specially crafted email be sent to a vulnerable Exchange server. The security update addresses the vulnerability by correcting how Microsoft Exchange Server handles objects in memory.
  • CVE-2019-1266: Microsoft Exchange Spoofing Vulnerability
    A spoofing vulnerability exists in Microsoft Exchange Server when Outlook Web App (OWA) fails to properly handle web requests. An attacker who successfully exploited the vulnerability could perform script or content injection attacks, and attempt to trick the user into disclosing sensitive information. An attacker could also redirect the user to a malicious website that could spoof content or the vulnerability could be used as a pivot to chain an attack with other vulnerabilities in web services. To exploit the vulnerability, an attacker could send a specially crafted email containing a malicious link to a user. An attacker could also use a chat client to social engineer a user into clicking the malicious link. However, in both examples the user must click the malicious link. The security update addresses the vulnerability by correcting how OWA validates web requests.

View: Description of the security update for Microsoft Exchange Server 2019 and Exchange Server 2016: September 10, 2019
Download: Security Update For Exchange Server 2016 CU13 (KB4515832)
Download: Security Update For Exchange Server 2016 CU13 (KB4515832)
Download: Security Update For Exchange Server 2019 CU1 (KB4515832)
Download: Security Update For Exchange Server 2019 CU2 (KB4515832)