Revolutionizing Security: Microsoft Bids Farewell to NTLM, Welcomes a Safer Tomorrow

Introduced in 1993 atop the LM framework, Windows NT LAN Manager (NTLM)—with iterations including LANMAN, NTLMv1, and NTLMv2—has ceased active development, shifting focus to security enhancements.

In October 2023, Microsoft disclosed intentions to entirely phase out the NTLM protocol, citing its obsolescence and security inadequacies, favoring protocols such as Kerberos or Negotiate instead.

The forthcoming Windows 11 24H2 and Windows Server 2025 releases, alongside Windows 11 LTSC 2024, will mark the final versions supporting NTLM, aiming to maintain compatibility.

Future editions will eschew the NTLM protocol, urging enterprises and developers to initiate protocol migration early for a seamless transition, despite the timeline for new releases spanning several years.

Microsoft recommends substituting NTLM protocol calls with Negotiate, which endeavors to authenticate via Kerberos, reverting to NTLM when necessary, thereby enhancing authentication security by leveraging advanced protocols like Kerberos, given NTLM's antiquity.

It's noteworthy that Kerberos, despite its superiority over NTLM, has been around for over two decades, having debuted in Windows 2000 SP4.