In addition to supporting Microsoft Office 97/2000/XP/2003 documents, PDF files, PKCS#12 certificates, PGP and LM/NTLM hashes used in Windows NT/2000/XP/2003 logon passwords, PGP Whole Disk Encryption, Microsoft Money and OneNote, Intuit Quicken, Lotus Notes ID files, MD5 hashes, the program can now handle new Microsoft Office 2007 encryption.
Microsoft Office documents security is considerably enhanced in version 2007. The encryption information block is the same as in Office XP/2003, but Office 2007 always uses AES encryption (is the strongest industry-standard algorithm available) with 128 bit key and SHA-1 hashing; besides, new version improves the algorithm of converting passwords into keys: 50000 SHA-1 sequential iterations are being performed now. You would never notice it when opening a file because the whole process requires less than a second. But in a password recovery process, the speed drops significantly: one can test only about 500 passwords per second even on cutting-edge processors such as Intel Core 2 Duo. Thus, one computer can find 4-5 letter passwords only, and so the only way to recover longer passwords to Office 2007 documents is using a cluster. 1000 computers are able to maintain the speed at 500,000 passwords -- comparable to the speed of password recovery on a single computer for older Microsoft Office documents.
Before Distributed Password Recovery, the most effective way to recover a lost password was to put the locked file on the fastest machine in the company, and use brute force to attack the password. Distributed Password Recovery lets you coordinate all of the unused computing power of every computer on your LAN or WAN, and use distributed processing to restore the lost password, which makes the brute-force attack very effective even for the documents where the strong encryption is being used, such as in Office 2007.
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