Reverse – Vault door 8

Vault door 8 – 450pt Challenge Apparently Dr. Evil’s minions knew that our agency was making copies of their source code, because they intentionally sabotaged this source code in order to make it harder for our agents to analyze and crack into! The result is a quite mess, but I trust that my best specialContinua a leggere “Reverse – Vault door 8”

Reverse – Vault door 7

Vault door 7 – 400pt Challenge This vault uses bit shifts to convert a password string into an array of integers. Hurry, agent, we are running out of time to stop Dr. Evil’s nefarious plans! The source code for this vault is here: VaultDoor7.java Hints Use a decimal/hexademical converter such as this one: https://www.mathsisfun.com/binary-decimal-hexadecimal-converter.html YouContinua a leggere “Reverse – Vault door 7”

Reverse – Vault door 6

Vault door 6 – 350pt Challenge This vault uses an XOR encryption scheme. The source code for this vault is here: VaultDoor6.java Hints If X ^ Y = Z, then Z ^ Y = X. Write a program that decrypts the flag based on this fact. Solution Again, there’s a list of numbers meant toContinua a leggere “Reverse – Vault door 6”

Reverse – Vault door 5

Vault door 5 – 300pt Challenge In the last challenge, you mastered octal (base 8), decimal (base 10), and hexadecimal (base 16) numbers, but this vault door uses a different change of base as well as URL encoding! The source code for this vault is here: VaultDoor5.java Hints You may find an encoder/decoder tool helpful,Continua a leggere “Reverse – Vault door 5”

Reverse – Vault door 4

Vault door 4 – 250pt Challenge This vault uses ASCII encoding for the password. The source code for this vault is here: VaultDoor4.java Hints Use a search engine to find an "ASCII table". You will also need to know the difference between octal, decimal, and hexademical numbers. Solution There’s a list of numbers in theContinua a leggere “Reverse – Vault door 4”

Reverse – Vault door 3

Vault door 3 – 200pt Challenge This vault uses for-loops and byte arrays. The source code for this vault is here: VaultDoor3.java Hints Make a table that contains each value of the loop variables and the corresponding buffer index that it writes to. Solution The function inside the source file scrambles the flag. To decodeContinua a leggere “Reverse – Vault door 3”

Reverse – Vault door 1

Vault door 1 – 100pt Challenge This vault uses some complicated arrays! I hope you can make sense of it, special agent. The source code for this vault is here: VaultDoor1.java Hints Look up the charAt() method online. Solution The flag is the sequence of chars in checkPassword, you just need to sort it becauseContinua a leggere “Reverse – Vault door 1”

Reverse – Vault Door training

Vault door training – 50pt Challenge Your mission is to enter Dr. Evil’s laboratory and retrieve the blueprints for his Doomsday Project. The laboratory is protected by a series of locked vault doors. Each door is controlled by a computer and requires a password to open. Unfortunately, our undercover agents have not been able toContinua a leggere “Reverse – Vault Door training”

Reverse – Time’s Up, One Last Time

Time’s Up, One Last Time – 500pts. Please take a minute to read the writeup of Time’s Up Again before reading this writeup First Look Let’s run the program and see what happens. osboxes@osboxes:/pico19/timesUp3$ ./times-up-one-last-time Challenge: (((((81350923) x (992025469)) * ((-345445693) f (-1965453472))) o (((-1637073355) t (953418846)) x ((-1728968449) ^ (-1556478121)))) o ((((-1265342796) o (-2122365540))Continua a leggere “Reverse – Time’s Up, One Last Time”

Reverse – Time’s Up, Again

Time’s Up, Again – 450pts. First Look Let’s run the program and see what happens. osboxes@osboxes:/pico19/timesUp2$ ./times-up-again Challenge: (((((-52815999) – (-455631185)) + ((506330670) – (287586908))) + (((-783690141) (1129961688)) + ((968135910) + (-532253008)))) ((((-611846001) – (1827816890)) – ((261971858) + (1452576703))) + (((-303988106) + (1002750425)) + ((1908742675) + (2058401240))))) Setting alarm… Solution? Alarm clock There does notContinua a leggere “Reverse – Time’s Up, Again”