binhexa

Published: April 3, 2024Updated: December 9, 2025

Description

How well can you perfom basic binary operations?

Additional details will be available after launching your challenge instance.

Port provided per instance

Launch the picoCTF instance so it assigns you a unique port number for your session.

Connect to titan.picoctf.net with that port via netcat to receive the randomized prompts.

nc titan.picoctf.net <PORT_FROM_INSTANCE>

Solution

  1. Step 1Understand the challenge
    Each run gives a series of six questions that perform operations on two binary numbers. The values below are from one walkthrough; your connection will use different operands. Use the Binary Calculator tool for most of these conversions since it handles AND/OR/XOR, addition, and bit shifts without mistakes.
  1. Compute 11010100 & 00100001

    Answer: 00000000

    Any overlapping 1 bits survive the AND; otherwise the result bit is 0.

  2. Compute 11010100 | 00100001

    Answer: 11110101

    OR preserves 1s from either operand. RapidTables' binary calculator makes this trivial.

  3. Multiply 11010100 * 00100001

    Answer: 1101101010100

    Binary multiplication mirrors base-10 long multiplication: stack the numbers and shift addends.

  4. Shift 11010100 left by 1 bit

    Answer: 110101000

    Appending a single 0 on the right multiplies the number by two.

  5. Compute 11010100 + 00100001

    Answer: 11110101

    Binary addition carries just like decimal math, so watch the carry chain in the middle bits.

  6. Shift 00100001 right by 1 bit

    Answer: 10000

    A right shift divides by two, chopping the least-significant bit.

Helpful resources

Flag

picoCTF{b1tw^3se_0p3eR@tI0n_su33essFuL_aea...}

After answering all six prompts correctly, the service asks for the hexadecimal form of the final value (10000₂ = 0x10). Submit that answer to receive the flag above.