Re: Passwords with Lan Manager (LM) under Windows

From: philippe.nospam.oechslin@objectif-securite.nospam.ch
Date: Fri Sep 23 2005 - 02:48:14 EDT


('binary' encoding is not supported, stored as-is) Hello Cedric!

The characterset used for LanMan passwords is the OEM character set used in original IBM PCs.

The reference to 142 characters probably refers to the number of chars that you could type on a standard keyboard.

In recent Window OSs there is no limitation about the character set. You can use any 8bit character that you are able to type in a text box or on a command line.

A quick test on my XP system show that characters above 127 can be used in "net user /add" command. Strangely enough some groups of them generate the same LMHash while generating different NThashes:

128,135
129,154
130,144
131,133,160
132,142
134,143
136,137,138
139,140,141,161
145,146
147,149,162
148,153
150,151,163
152,255
164,165
228,229
232,237

which yields 106 different character above 127.

from the lower 128 chars, tab, space and delete are not easy not enter in an input field.

This leaves us with a total of 231 working characters...

 cheers,

   Philippe

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