GETTING STARTED
Getting Started with CryptoCrack
In this section we'll show you how to use CryptoCrack. To get started you'll need to start CryptoCrack.
Select CryptoCrack from the Windows 11/10 Start Menu.
Accessing Functions using the Keyboard
Most of the functions in the ribbon command bar can be accessed by pressing the Alt key followed by a keytip letter. For example pressing Alt shows the tab keytips.
Selecting a tab keytip reveals the function keytips. For example, after pressing the Alt key, pressing H selects the Home tab and shows the function keytips.
Solve a Known Cipher Type
In this example we’ll use CryptoCrack to solve the following cipher which we believe is a Monoalphabetic Substitution or Aristocrat cipher.
LZXLDCRX FEVLZK XVJJSRCI LGZ XDCLRCZCLK BRIJVLZ DOZJ LGZ ZVJLG’K KNJMVXZ V MZP RCXGZK FZJ SZVJ, VWDNL LGZ KVBZ KFZZY LGVL V MRCIZJCVRE IJDPK.
Ciphers can be loaded into CryptoCrack either by pasting the ciphertext directly into the Ciphertext box on the main window or by reading the ciphertext from a file.
Pasting Ciphertext From the Clipboard
Ciphertext can be loaded into CryptoCrack from the clipboard by pasting the ciphertext into the Ciphertext box on the main window, using Ctrl+V or clicking the Paste button. Clicking away from the Ciphertext box will reveal the character frequency count.
Reading Ciphertext From a File
To read the ciphertext from a file:
Click on the File drop down menu (top left-hand corner).
Click Open.
Select the file from the dialog box.
The ciphertext will be read from the file and placed in the Ciphertext box and the character frequency count will be displayed.
The File menu will also add the file path to the Recent Documents list as shown in the screenshot. This will display the ten most recent files opened though this number can be changed in the Options window.
Character Frequency
The character frequency count will be updated when a new ciphertext is read into CryptoCrack. This is limited to the following characters:
A-Z, 0-9, spaces and , .'-!"#()*/:;?=.
Both the displayed ciphertext and the character frequency only show the characters valid for the selected cipher type as displayed in the Cipher Type group in the ribbon command bar. If Unknown is selected as the cipher type then all characters will be displayed; letters, numbers and punctuation.
Solve the Cipher
We suspect the example cipher is a Monoalphabetic Substitution cipher with word divisions or Aristocrat.
Click the Cipher Type drop-down menu in the Cipher Type group in the ribbon command bar. and select Aristocrat.
This will update the character frequency display to only show those characters valid for the Aristocrat cipher.
Click Solve.
The program will now try to solve the cipher using a hill climbing algorithm.
To stop the program click Stop Solving.
The Best match box will show the plaintext with the highest score; best match to English.
The Best key shows the key used to produce this solution.
The Top solutions lists the top ten best scoring plaintexts and their score. To show more results click on the All Solutions button in the ribbon. By default this shows the top 50 solutions with their keys and scores.
Solve an Unknown Cipher
In this example we’ll use CryptoCrack to solve the following cipher of unknown cipher type.
WRMDL KUEWM LVKHA SXRLP ZKEZK VNLKJ ANHIW XIOOU PAPLI LPOWL SCTKI GPEBU ITYER MGJAZ WRLKE MWJHG UBKSN QAYAK SEKPZ VNLBV WSFHM NWQJL LZKPL ZOXEP LMXLY GNENA SEEER CZLTF ZXPKU KWHEF GMMWN ENKDP WAOAS VOWQT BUAXF LSCTK IGPEB UITYO XPKUM JUJQL ARHKY VJWHL WXWHH ZKWRL KCXFP YIRSR LNCBU NXLPS ENLKW USCIH GDEJB GVGWD YVJYX VLSCT KIGPE BUITY ERMGJ AZWRL GUWZK PLEVN JWVUY ZMJWM ONAYG NQWXL MZWRI LBEDI MVAAX GJGME VNXAI TIVGX EHMTA TLPLI ZSXNA PXAAT HKXIZ VBFAE KNITY
Read the ciphertext into CryptoCrack either by pasting it into the Ciphertext box or by reading it from a file using the File menu.
In this example the cipher type is unknown so we have to determine this before it can be solved.
Click on the Tools tab.
Click Identify Cipher in the App Tools group in the ribbon command bar.
This shows the cipher type possibilities with the most likely types towards the top of the list with the lowest score. In this case there are a number of types to choose from with similar scores but the most common is the Vigenère cipher. We'll choose that one to try first.
Click the Home tab.
Click the Cipher Type drop-down menu in the Cipher Type group in the ribbon command bar and select Vigenère.
This will update the character frequency display to only show those characters valid for the Vigenère cipher (A-Z only).
As the Vigenère cipher is a periodic cipher, meaning it's based on a key length, the Cipher Settings ribbon group enables a period to be selected. By default 0 (zero) is shown which means that all key lengths between 4 and 15 will be tested. This range can be changed in Tools - Options. Otherwise if the key length is known its value can be selected making the solving quicker.
Click Solve.
The program will now try to solve the cipher using a hill climbing algorithm.
To stop the program click Stop Solving.
If no solution is found it may not be a Vigenère cipher so another cipher type can be tried.
Edit the Solution
After solving the best solution found is :
anexerciseforpeoplewhoareoutofshapebeginwithafivepoundpotatobagineachhandextendyourarmsstraightoutfromyoursidesholdthemthereforafullminuteandthenrelaxafterafewweeksmoveuptotenpoundpotatobagsthentryfiftypoundpotatobagsandeventuallytrytogettowhereyoucanliftaonehundredpoundpotatobagineachhandandholdyourarmsstraightformorethanafullminuteonceyoufeelconfidentatthatlevelputapotatoineachbag
Read the ciphertext into CryptoCrack either by pasting it into the Ciphertext box or by reading it from a file using the File menu.
In this example the cipher type is unknown so we have to determine this before it can be solved.
Click on the Edit tab.
Click Sentence Case in the Edit Solution group in the ribbon command bar.
This changes the first character of the solution to uppercase.
Click Add Word Breaks.
This will add single spaces where it thinks word divisions should be.
Some of the words may be underscored with a red wavy line. This indicates that the word is misspelled or unrecognised such as where the inserted space is in the wrong place or the word is a proper name so should be capitalised.
Right-click the mouse over a misspelled word.
The spell checker shows some possible corrections.
Choose a correction to change the text.
Note: You need to have the .NET Framework 4.0 English language pack installed on your machine. For those without this there's an option to turn the spell check off in the Options window.
Also you may need to edit the text manually to correct any outstanding errors.
To save the solution...
Click Copy Solution.
This will copy the Best key and Best match to the clipboard.
WEIGHTS An exercise for people who are out of shape: Begin with a five-pound potato bag in each hand. Extend your arms straight out from your sides, hold them there for a full minute, and then relax. After a few weeks, move up to ten-pound potato bags. Then try fifty-pound potato bags, and eventually try to get to where you can lift a one hundred-pound potato bag in each hand and hold your arms straight for more than a full minute. Once you feel confident at that level, put a potato in each bag.
