Writeup in progress
Currently making the solution for Flags and the walkthrough will be published here as soon as it's ready.
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Flags
Published: April 2, 2026
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Useful tools for Cryptography
- ROT / Caesar CipherDecode Caesar-shifted and ROT-encoded text. Drag the shift slider or scan all 26 rotations at once.
- Base64 & Base32 DecoderDecode Base64 and Base32 strings with auto-detection. Multi-layer mode unwraps nested encodings automatically.
- XOR CipherXOR-decrypt hex or text ciphertext with a known key, or brute-force the single-byte key automatically.
- Vigenère CipherEncrypt or decrypt text with the Vigenère polyalphabetic substitution cipher using a keyword.
More Cryptography
- CryptographyEasy
13
Apply ROT13 - a Caesar cipher with a fixed shift of 13 - to each letter in the ciphertext to recover the plaintext picoCTF flag.
- CryptographyEasy
The Numbers
A1Z26 substitution. Map each number to its letter (1=A, 2=B...) to spell out THENUMBERSMASON.
- CryptographyMedium
caesar
Brute-force all 26 Caesar shifts. The correct one produces readable English inside the flag braces.