Word documents & Blind Swordsman

I was asked last week to see if I could get into a Word document that was password protected. The person who put the password on the document has since forgotten it. I said I’d take a look into it.

It was a Word 97/2000 document, which means that it uses a RC4 algorithm with a 40-bit key. That means there are only 2 ^ 40 (1,099,511,627,776) possible encryption keys, regardless or password length or complexity.

So I fired up my copy of the Advanced Office Password Breaker and started going through keys. After 385,950,206,720 attempts the program told me it had found the key and was ready to decrypt the document.

I click on the decrypt button and get this:

That hurts!

Since I had some time on my hands this weekend with my computer tied up crunching RC4 keys I decided to check out the Blind Swordsman: Zatoichi. It was pretty good, kind of reminded me of Shogun Assassin.