tl;dr

• Reverse bytearray to recover matrix cflag.
• Use first element of matrix to recover e (bruteforce &iroot)
• Reduce the flag to finite field of a 32-bit prime, solve for each character.

tl;dr

• Challenge involves Reversing, Web, and Crypto
• Reverse the binary to get the endpoints
• Trigger the XSS bug in the website and get admin cookie
• Use Hash Length extension attack to get authenticated as admin and get the flag

tl;dr

• Challenge is a Nintendo GameBoy ROM image.
• Reverse the ROM and figure out the implementation
• Analyze the calling function’s checks to find the path along which we must move.

tl;dr

• Hand-crafting a linux shared object file with a size of less than 194 bytes