Challenge "Elliptic Boogaloo – Part 1"
By: admin on Nov. 27, 2023, 3:13 p.m.
Ready for the Elliptic Boogaloo? In this challenge, we dance on elliptic curves and try to forge digital signatures.
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Challenge "A disguised code"
By: admin on Oct. 31, 2023, 9:27 a.m.
This challenge is a puzzle about a mysterious ciphertext, which is also protected by a clever disguise. Can you crack it?
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Challenge "The Hutton Cipher – Part 5"
By: admin on Oct. 16, 2023, 11:07 a.m.
An English plaintext of length 4272 was encrypted with the Hutton cipher, a pen-and-paper cipher from 2018. The length of the two passwords is also known. Can you successfully perform a ciphertext-only attack?
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Challenge "The Hutton Cipher – Part 4"
By: admin on Sept. 6, 2023, 10:49 a.m.
Unlock the secrets of the Hutton cipher, a pen-and-paper cipher from 2018. Can you crack the ciphertext?
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Challenge "The Hutton Cipher – Part 3"
By: admin on July 21, 2023, 11:08 a.m.
Unlock the secrets of the Hutton cipher, a pen-and-paper cipher from 2018. Can you crack the ciphertext?
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Challenge "The Hutton Cipher – Part 2"
By: admin on June 5, 2023, 2:27 p.m.
Unlock the secrets of the Hutton cipher, a pen-and-paper cipher that has baffled cryptographers since 2018. Can you reconstruct the keywords used?
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Challenge "The Hutton Cipher – Part 1"
By: admin on May 2, 2023, 4:11 p.m.
Unlock the secrets of the Hutton cipher, a pen-and-paper cipher that has baffled cryptographers since 2018. Can you crack the ciphertext?
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Challenge "The Josse Challenge – Part 3"
By: admin on March 27, 2023, 10:05 a.m.
The Josse cipher is a polyalphabetic cipher from the time of the Franco-Prussian War. Its description was lost. It was only rediscovered and published in 2020. In these challenges you are to decipher several, increasingly shorter ciphertexts.
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Challenge "The Josse Challenge – Part 2"
By: admin on Feb. 25, 2023, 1:29 a.m.
The Josse cipher is a polyalphabetic cipher from the time of the Franco-Prussian War. Its description was lost. It was only rediscovered and published in 2020. In these challenges you are to decipher several, increasingly shorter ciphertexts.
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Challenge "The Josse Challenge – Part 1"
By: admin on Feb. 10, 2023, 8:47 a.m.
The Josse cipher is a polyalphabetic cipher from the time of the Franco-Prussian War. Its description was lost. It was only rediscovered and published in 2020. In these challenges you are to decipher several, increasingly shorter ciphertexts.
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Challenge "A Heavy SZ42 Challenge – Part 14"
By: admin on Dec. 30, 2022, 12:59 p.m.
The Lorenz SZ42, codenamed Tunny, was a German teleprinter encryption device used during WW2. This is the fourteenth challenge in a series of 16 level-3 challenges with the SZ42. In this "Breaking" challenge you are only provided with one ciphertext…
Challenge "The Syllabary Cipher -- Part 5"
By: admin on Oct. 28, 2022, 1:34 p.m.
The Syllabary cipher seems to be just another substitution cipher. This time, the table got mixed up. Is a solution even possible? Find it out!
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Challenge "The Syllabary Cipher -- Part 4"
By: admin on Oct. 28, 2022, 1:32 p.m.
The Syllabary cipher seems to be just another substitution cipher, but is it? Find out and solve its mystery! All keys went missing...
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Challenge "The Syllabary Cipher -- Part 3"
By: admin on Oct. 28, 2022, 1:30 p.m.
The Syllabary cipher seems to be just another substitution cipher, but is it? Find out and solve its mystery! But this time, the table is weird...
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Challenge "The Syllabary Cipher -- Part 2"
By: admin on Oct. 28, 2022, 1:29 p.m.
The Syllabary cipher seems to be just another substitution cipher, but is it? Find out and solve its mystery! A key got missing...
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