Microsoft confirms memory leak in March Windows Server security update

Infosec in brief If your Windows domain controllers have been crashing since a security update was installed earlier this month, there's no longer any need to speculate why: Microsoft has admitted it introduced a memory leak in its March patches and fixed the issue. Reports of the bug poured in across recent days as sysadmins reported Windows Server systems freezing and restarting. Microsoft has since confirmed the issue is to do with the Local Security Authority Subsystem Service process on Windows Server 2012 R2 (no longer under support), 2016, 2019 and 2022. The issue is being triggered "when on-premises and cloud-based Active Directory Domain Controllers service Kerberos authentication requests," Microsoft noted in posts detailing known issues with its Server OS, including KB5035849, KB5035855 and KB505857. "Extreme memory leaks may cause LSASS to crash, which triggers an unscheduled reboot of underlying domain controllers," Redmond noted, adding that the root cause has been identified and a patch will be issued in coming days. A patch has now been delivered. Until you install that fix, the only way to prevent a domain controller from crashing is to monitor its memory usage and keep an eye out for leaks. Of course, if you don't have the patience or staff to dedicate to such an endeavor, there is another option: uninstall the patches that introduced the issue. As one Reddit user on r/sysadmin pointed out, the fix is relatively simple. From a command prompt run as an admini...