Authentication Encryption Algorithms

Question 1

What is LM?

Answer 1

Lan Manager (AKA LANMAN), a authentication encryption method using a hash challenge similar to CHAP. Somewhat insecure, no longer used.

Question 2

What is NTLM?

Answer 2

NT Lan Manager, passwords are more secure. Password is Unicode, up to 127 characters long, and is stored as a 128-bit MD4 hash.

Question 3

What is NTLMv2

Answer 3

Version 2 of NTLM, with a new password response. Uses MD4 password hash, HMAC-MD5 hash of username and server name, and has a variable-length challenge of timestamp, random data, and domain name.

Question 4

What are NLTM’s vulnerabilities?

Answer 4

Some Windows password databases contain LM hash versions of the passwords

Also vulnerable to credentials forwarding attack (use credentials of one computer to gain access to another)

Question 5

What is a credentials forwarding attack?

Answer 5

Use credentials of one computer to gain access to another.