Passworded Word Docs
Discussion
I tried looking at the header files of a document once to see if you could extract the password.
hmmmmmmmmm
Im sure it is possible, but I’m not sure how.
My tool just cycled through dictionary names then started going through all the permutations, that takes a long time though especially if you add numerical’s as well.
hmmmmmmmmm
Im sure it is possible, but I’m not sure how.
My tool just cycled through dictionary names then started going through all the permutations, that takes a long time though especially if you add numerical’s as well.
Couple of things about this - Microsoft put password protection into Office 95 products to provide a level of security to prevent editing. It used a basic obfuscation technique (similar to ROT13 if anyone knows this). Basically the cracking tools for this were a case of running through the document and trying to match words up with combinations - i.e. looking for things like "the" and working backwards to the password used.
The advent of Office 98 and above introduced a decent password protection system that used a proprietary protocol for basically encrypting the word document from the password. This wasnt strong because the password was used as the key and hence you can decipher the document from working backwards again - stronger but not strong.
Office XP uses a strong password mechanism with a decent encryption system. This too can be attacked as crypto-analysis can be very effective against a document - you look for words and patterns and try and crack it backwards from there - by definition a Word document is English (or whatever) and therefore structure and content are relatively easy to break!
To be 100% honest, if you want protection for Office documents, dont use the Microsoft supplied systems. They are OK, but not strong enough. You should really look at commercial systems for encryption and protect them that way. However, for basic functionality they are sufficient.
P.S. Crypto-analysis is something that I have done in the past - its really dull
The advent of Office 98 and above introduced a decent password protection system that used a proprietary protocol for basically encrypting the word document from the password. This wasnt strong because the password was used as the key and hence you can decipher the document from working backwards again - stronger but not strong.
Office XP uses a strong password mechanism with a decent encryption system. This too can be attacked as crypto-analysis can be very effective against a document - you look for words and patterns and try and crack it backwards from there - by definition a Word document is English (or whatever) and therefore structure and content are relatively easy to break!
To be 100% honest, if you want protection for Office documents, dont use the Microsoft supplied systems. They are OK, but not strong enough. You should really look at commercial systems for encryption and protect them that way. However, for basic functionality they are sufficient.
P.S. Crypto-analysis is something that I have done in the past - its really dull
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