| |
 WINZIP® AND PKZIP® PASSWORD RECOVERY
|
| |
|
WINZIP® and PKZIP® programs feature fairly robust encryption but there are four ways to extract data and passwords from these files.
|
| |
|
The first way is by performing a known plaintext attack. A known plaintext attack is accomplished by using an unencrypted version of one of the files in a zip archive to decrypt the others. As an example, let’s assume that three files are encrypted into an archive using the same password. The client has an exact unencrypted copy of one of the files, but wants the other two. We can then perform a known plaintext attack on the archive to decrypt not only the other two files, but to acquire the original password.
|
| |
|
Why, you might ask, would someone want to decrypt an archive if they already have an unencrypted copy of the files? First, a zip archive might contain hundreds or thousands of files. Only one is needed to perform the known plaintext attack. Frequently archives are created of all of the files on a hard-disk or of all of the files pertaining to a particular project. Some of these files might be unique and no other copies might exist. However, many files on a computer are very common to other computers (driver files, software files, templates, graphics, icons, etc.) Therefore, one or more files from an archive might be able to be obtained from another source or might be very common and easily reproduced even if the owner of the zip archive doesn’t have those files. Further, the password used to encrypt one archive, might be the key to decrypting another archive or another file for which no plaintext exists.
|
| |
|
A known plaintext attack is complicated to run, but is usually successful.
|
| |
|
The second method is called a dictionary attack. In this attack, passwords from a VERY large list of words in numerous languages, phrases, numbers, names, quotes and other sources of common passwords are used to attempt to guess the password. Multiple combinations of capitalization and combinations of words are tested. Because of the speed of the software programs we use to perform this work, this can be done relatively quickly. We have compiled dictionaries from numerous sources into a single large dictionary which can be used for this type of attack. Typically, people are very similar and most people still choose a word, name or number that is short and easy to remember. This method may provide the password.
|
| |
|
The third method is called a brute force attack. In this attack, every possible combination of characters is tested against the password until a match is found. This can take a very long time and this method will only be successful on short passwords. Some level of enhancement and skill can be added to this method by carefully planning the sequence of guesses and the character sets used. While this method will eventually be 100% effective, the length of time needed utilizing existing technology can sometimes exceed the age of the universe. While this method is, therefore, only practical with short passwords, we have had success with this method in the past.
|
| |
|
The last method only works on some archives. If you have an archive created by WINZIP® and it contains more than 5 files all encrypted at the same time and with the same password, there is a special recovery method that we can use on this type of file to recover the password.
|
| |
|
Our fee for attempting the known plaintext, dictionary, brute force and special guaranteed attacks is $100.00 if we find your password. If these attempts fail, you pay nothing. Typically we will test our entire dictionary and brute force passwords up to 7 characters long (a couple of days of processing time though we may recover your password at any time during the process).
|
| |
|
Our service is guaranteed -- if we fail to recover your passwords you pay nothing. Please contact us by email at pwcrack@pwcrack.com if you would like us to recover WINZIP® or PKZIP® passwords for you or complete our standard agreement form and send your .zip file(s).
|
| |
|
If you would prefer to recover WINZIP® or PKZIP® passwords yourself, you can purchase WINZIP® or PKZIP® password recovery software from Passware, Inc.
|
| |
|
Please read our instructions before sending files or payments.
|
