Everything you need to know about the Microsoft Exchange Server hack

Update 26.3.2024: While not on the same scale as 2021's Microsoft Exchange Server hack (see below this update), security problems impacting Exchange Server have reemerged. In March 2024's monthly patch cycle, Microsoft resolved critical issues in software including HyperV and Exchange Server. These fixes follow the release of a 2024 H1 Cumulative Update for Exchange Server in February. The 2024 H1 Cumulative Update includes Extended Protection (EP) being enabled by default. EP is a Windows feature for protecting servers from man-in-the-middle (MiTM) attacks. The automatic inclusion of EP was first announced in 2023. Also: The best VPN services of 2024: Expert tested and reviewed The security upgrade can help resolve CVE-2024-21410, a privilege escalation vulnerability leading to NTLM relay attacks that impacts Exchange Server. This vulnerability is being actively exploited in the wild. "An attacker could target an NTLM client such as Outlook with an NTLM credentials-leaking type vulnerability," Microsoft says. "The leaked credentials can then be relayed against the Exchange server to gain privileges as the victim client and to perform operations on the Exchange server on the victim's behalf." CVE-2024-21410 was revealed in the February 2024 Microsoft patch update. Original article, first published in 2021: Four zero-day vulnerabilities in Microsoft Exchange Server are being actively exploited by state-sponsored threat groups and others to deploy backdoors and malware in wides...