Also known as NT LAN Manager
In a Windows network, NT (New Technology) LAN Manager (NTLM) is a suite of Microsoft security protocols intended to provide authentication, integrity, and confidentiality to users. NTLM is the successor to the authentication protocol in Microsoft LAN Manager (LANMAN), an older Microsoft product. The NTLM protocol suite is implemented in a Security Support Provider, which combines the LAN Manager authentication protocol, NTLMv1, NTLMv2 and NTLM2 Session protocols in a single package. Whether these protocols are used or can be used on a system, which is governed by Group Policy settings, for whi

[MS-NLMP]: NT LAN Manager (NTLM) Authentication Protocol | Microsoft Learn
Specifies the NT LAN Manager (NTLM) Authentication Protocol, used in Windows for authentication between clients and servers.
msdn.microsoft.com →Specifies the NT LAN Manager (NTLM) Authentication Protocol, used in Windows for authentication between clients and servers. NTLM is used by application protocols to authenticate remote users and, optionally, to provide session security when requested by the application. Click here to download a zip file of all PDF files for Windows Protocols. From time to time, Microsoft may publish a preview, or pre-release, version of an Open Specifications technical document for community review and feedback. To submit feedback for a preview version of a technical document, please follow any instructions specified for that document. If no instructions are indicated for the document, please provide feedback by using the Open Specification Forums . The preview period for a technical document varies. Additionally, not every technical document will be published for preview. A preview version of this document may be available on the Windows Protocols - Preview Documents page. After the preview period, the most current version of the document is available on this page. Plugfests and Events , Test Tools , Development Support , and Open Specifications Dev Center . Technical Documentation. Microsoft publishes Open Specifications documentation (“this documentation”) for protocols, file formats, data portability, computer languages, and standards support. Additionally, overview documents cover inter-protocol relationships and interactions. No Trade Secrets . Microsoft does not claim any trade secret rights in this documentation. Patents . Microsoft has patents that might cover your implementations of the technologies described in the Open Specifications documentation. Neither this notice nor Microsoft's delivery of this documentation grants any licenses under those patents or any other Microsoft patents. However, a given Open Specifications document might be covered by the Microsoft Open Specifications Promise or the Microsoft Community Promise . If you would prefer a written license, or if the technologies described in this documentation are not covered by the Open Specifications Promise or Community Promise, as applicable, patent licenses are available by contacting [email protected] . License Programs . To see all of the protocols in scope under a specific license program and the associated patents, visit the Patent Map . Trademarks . The names of companies and products contained in this documentation might be covered by trademarks or similar intellectual property rights. This notice does not grant any licenses under those rights. For a list of Microsoft trademarks, visit www.microsoft.com/trademarks . Fictitious Names . The example companies, organizations, products, domain names, email addresses, logos, people, places, and events that are depicted in this documentation are fictitious. No association with any real company, organization, product, domain name, email address, logo, person, place, or event is intended or should be inferred. Reservation of Rights . All other rights are reserved, and this notice does not grant any rights other than as specifically described above, whether by implication, estoppel, or otherwise. Tools . The Open Specifications documentation does not require the use of Microsoft programming tools or programming environments in order for you to develop an implementation. If you have access to Microsoft programming tools and environments, you are free to take advantage of them. Certain Open Specifications documents are intended for use in conjunction with publicly available standards specifications and network programming art and, as such, assume that the reader either is familiar with the aforementioned material or has immediate access to it.
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In a Windows network, NT (New Technology) LAN Manager (NTLM) is a suite of Microsoft security protocols intended to provide authentication, integrity, and confidentiality to users. NTLM is the successor to the authentication protocol in Microsoft LAN Manager (LANMAN), an older Microsoft product. The NTLM protocol suite is implemented in a Security Support Provider, which combines the LAN Manager authentication protocol, NTLMv1, NTLMv2 and NTLM2 Session protocols in a single package. Whether these protocols are used or can be used on a system, which is governed by Group Policy settings, for which different versions of Windows have different default settings.
NTLM passwords are considered weak because they can be brute-forced very easily with modern hardware.
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Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).