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RAINBOW TABLES  LM & NTLM HASHES 	     By:-			Rahul Sharma			   TE COMPUTERS		    T3224245
How Windows Store Passwords?? ,[object Object]
Old technology used on LAN Manager
NT hashes
Unicode password or MD4 hash
Used for authentication on more recent Windows systems,[object Object]
LM “Hash” Generation
how to create the hash
LM hashes
Overview
Proof that case doesn’t matter Password = E52CAC67419A9A22  4A3B108F3FA6CB6D  PaSSwORd = E52CAC67419A9A22  4A3B108F3FA6CB6D  Password1 = E52CAC67419A9A22  38F10713B629B565
NTLM HASHES Uses MD4 algorithm to create a hash of the mixed-case password Results in a 16 byte hash of the password (stored in the SAM…) Used for any password greater than 14 characters
NTLM HASH
Proof that case DOES matter Password = F15ABD57801840F3 348DDCCAFB677F6A  PaSSwORd = 17504CE07C0A0D4A 1BD3A99A0821F957  Password1 = F9A3152D926F9FF8 98D0BAFBA0BFFD30
NTLM Hash Considerations Case preserving Maximum length = 127 characters Better Security than LM Hashes Number of ≤14-character password (full char set) ≈ 2.7*1067 Number of 127-character passwords ≈ 4.9*10611
ATTACKS ON PASSWORDS….
[object Object]
Types of Brute Force attacks:                   Online B.F.                  Offline B.F. ,[object Object],limit number of login attempts
Reduce Hash Hash Reduce Reduce
Algorithm followed:-
Hash Reduce Reduce Hash Reduce Hash Reduce Hash
IS THIS EFFECTIVE???
How to prevent rainbow tables from cracking passwords??
What is SALT?? Special text or code. It does password strengthening SOME FACTS:- ,[object Object]
This makes it possible to speed up password cracking with precomputed Rainbow Tables
LINUX uses SALT….,[object Object]

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