This page contains lists of recent and most difficult challenges. To play the challenges, please go to the challenges section.

Category | Challenge | Points | Solves |

General | Transparency | 50 | 224 solves |

RSA | Let's Decrypt Again | 175 | 37 solves |

Misc | Twin Keys | 100 | 30 solves |

Misc | Invariant | 250 | 25 solves |

Misc | No Difference | 175 | 35 solves |

Misc | Trust Games | 150 | 28 solves |

Misc | PriMeD5 | 100 | 58 solves |

Mathematics | Ellipse Curve Cryptography | 125 | 54 solves |

RSA | Let's Decrypt | 80 | 74 solves |

Elliptic Curves | No Random, No Bias | 120 | 47 solves |

Elliptic Curves | Edwards Goes Degenerate | 100 | 35 solves |

Mathematics | Size and Basis | 15 | 515 solves |

Mathematics | Gaussian Reduction | 50 | 314 solves |

Mathematics | Find the Lattice | 100 | 167 solves |

Mathematics | Vectors | 10 | 534 solves |

Mathematics | Backpack Cryptography | 120 | 105 solves |

Mathematics | Gram Schmidt | 30 | 336 solves |

Mathematics | What's a Lattice? | 40 | 369 solves |

Mathematics | Unencryptable | 125 | 120 solves |

Misc | Too Many Errors | 100 | 73 solves |

Block Ciphers | Forbidden Fruit | 150 | 77 solves |

Misc | Collider | 50 | 174 solves |

Misc | MD0 | 80 | 102 solves |

Block Ciphers | Triple DES | 60 | 118 solves |

Mathematics | Modular Square Root | 35 | 584 solves |

Mathematics | Broken RSA | 100 | 221 solves |

Mathematics | Real Eisenstein | 150 | 80 solves |

Block Ciphers | Keyed Permutations | 5 | 918 solves |

Block Ciphers | Structure of AES | 15 | 630 solves |

Block Ciphers | Round Keys | 20 | 569 solves |

Block Ciphers | Resisting Bruteforce | 10 | 837 solves |

Block Ciphers | Confusion through Substitution | 25 | 493 solves |

Block Ciphers | Bringing It All Together | 50 | 370 solves |

Block Ciphers | Diffusion through Permutation | 30 | 443 solves |

RSA | Bespoke Padding | 100 | 133 solves |

Misc | Nothing Up My Sleeve | 150 | 72 solves |

Elliptic Curves | Moving Problems | 150 | 91 solves |

Block Ciphers | Paper Plane | 120 | 123 solves |

Mathematics | Prime and Prejudice | 200 | 102 solves |

General | XOR Properties | 15 | 1969 solves |

Misc | Toshi's Treasure | 150 | 103 solves |

Mathematics | Legendre Symbol | 35 | 742 solves |

Mathematics | Quadratic Residues | 25 | 1086 solves |

RSA | Crossed Wires | 100 | 360 solves |

Elliptic Curves | Elliptic Nodes | 150 | 99 solves |

Diffie-Hellman | Static Client 2 | 120 | 120 solves |

Misc | Bit by Bit | 100 | 119 solves |

Misc | Lo-Hi Card Game | 120 | 129 solves |

Elliptic Curves | Micro Transmissions | 120 | 104 solves |

Elliptic Curves | Curveball | 100 | 121 solves |

Category | Challenge | Points | Solves |

Misc | Invariant | 250 | 25 solves |

Misc | Trust Games | 150 | 28 solves |

Misc | Twin Keys | 100 | 30 solves |

Elliptic Curves | Edwards Goes Degenerate | 100 | 35 solves |

Misc | No Difference | 175 | 35 solves |

RSA | Let's Decrypt Again | 175 | 37 solves |

Elliptic Curves | No Random, No Bias | 120 | 47 solves |

Mathematics | Ellipse Curve Cryptography | 125 | 54 solves |

Misc | PriMeD5 | 100 | 58 solves |

Misc | Nothing Up My Sleeve | 150 | 72 solves |

Misc | Too Many Errors | 100 | 73 solves |

RSA | Let's Decrypt | 80 | 74 solves |

Block Ciphers | Forbidden Fruit | 150 | 77 solves |

Mathematics | Real Eisenstein | 150 | 80 solves |

Elliptic Curves | Moving Problems | 150 | 91 solves |

Elliptic Curves | Elliptic Nodes | 150 | 99 solves |

Misc | MD0 | 80 | 102 solves |

Mathematics | Prime and Prejudice | 200 | 102 solves |

Misc | Toshi's Treasure | 150 | 103 solves |

Elliptic Curves | Micro Transmissions | 120 | 104 solves |

Mathematics | Backpack Cryptography | 120 | 105 solves |

Elliptic Curves | ProSign 3 | 100 | 107 solves |

Block Ciphers | Triple DES | 60 | 118 solves |

Misc | Bit by Bit | 100 | 119 solves |

Mathematics | Unencryptable | 125 | 120 solves |

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