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Stuff to do while you wait (with a message from Harry added)

The Empty Vault Forums Bureau of Security and Signals Intelligence Forum Stuff to do while you wait (with a message from Harry added)

  • This topic has 4 replies, 3 voices, and was last updated 1 week, 1 day ago by BreakTheCipher.
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  • #69213
    madness
    Participant

    [A message from Harry: This topic typically contains some tougher challenges set by experienced competitors for one another. Don’t be surprised or alarmed if you don’t know how to break them, they are not part of the competition! Have fun, Harry].

    Is it too soon to post ciphers for fun?

    I recently found an interesting challenge involving a nicer version of the Alberti cipher. The details of the cipher are in this PDF:

    https://mysterytwister.org/media/challenges/pdf/mtc3-uelkes-02-alberti-02-en.pdf

    Just for you, I made a warm-up ciphertext. It’s longer, therefore easier. But be warned: some tricks you develop to
    crack it might not work for the shorter ciphertexts. Let’s call this one “ciphertext 0”.

    GwklqbYxgvxvjTizyjkcsDrmrxEaeccJqtgztAiivtfymayGlnpkYlceyKbnvbwwPdspevoviTlfjkfawkoWknuunjlruSelinibqQ
    skkxkexDyzhbDraitcfybTfaimCkigllSdlinAmftmOmpzhlBvcrjdtzAhlhzkaqvTaxxsijgxdFknzwvCttlmpbpAmaqtzhDrflnr
    cwbDhwerXipsctFtvgxlsLozgjneHyyrcrumJnckiNhpqtsofXattoKqmblbabuPimkiLsrvdzqjedEgfaaaffnfCwtlfeYbqqgGvl
    squkpMlwafduPzkshmDgliabrcYxgpqvcygpWunnbnjrLzuecmjEcnfezhgLxzvuUakdamPaoskpKqjnbgkhzlQcvlxacGiydlnpkM
    jxuwqxCvzvgtyvwPmakhdipBzdobCdbyktketyMnymdsjacYlkvmycpSspuvfKgbjgwqmVtglgryonZlwoyYofxgpaveoYbblpTckx
    wqcFagvzjxOdlqslseJgvsrkcvenNoxytbSebflplgsuNgyqssssOmbhlMutupRgtljrzwvgRfvqolXejptCiltsvVybyutgnowMus
    swvjxayPrgsyivhdyGisinbjkOelymRtxczvjrJigkyNpopjypVlgugwgugtOqhhqrbhmbBtsjvdpzPrikodyoWaenjLjfrxYgxofO
    lslpyfKvbgkAvdkdmhlTaisjecAfozpJtlxtgztPuuzmtdZwazgYpexhbEnibefoaouLvxmdrvAmjhwauhKwnhxgrBzacslzPhhmox
    ijZwsqnyhwdiIhfzzKqzzkbXzbpucjzgjHifmpsfrRghjrGjowkvirSvfwpinLnebevsOhqymqsuyPdeghixehNqtweTgjsexqjdIj
    picspiiVmugbogfgNpqtswfwpRrujboqrOfubedzljbCguktketydIgdyxcdWljlbhcxnhAmyfoayZmzgyazyYfbulebkXtcjqqjTj
    ddysjLrdepnugLpiuziejbKqukzzkzugIprfyPahderikZmzxdgexmiXibpawTmjqqikcesScuxclsOyqsdfPdgezziYcyxgpboyaE
    ugugsahniOrchyRrkkolvgqmMuwq

    Here are the ciphertexts from the PDF:

    1. CpicpwwWendgrinodkxLvmozqzgpdeojrqzIlyxisdifadcfydxUprbkqdcvqqgsoQawdbtzwkcoxkvzZwahuwagmnyh

    2. FersgAiqnoiqjgzpzUnkzrhvhrhlaxnIaibjcwyzcqwpolUkljnzdjqlaNrvf

    3. IpvyzxpyxqTgwukxsaxmttatwNkaoeixebdundyVyjhyuf

    4. KmhzhpbhBhlmnauidawaumqcmWzukjtfdasd

    5. OxjizwadbaGeuhjethqcbsxNliswbei

    So you can check your solution, here are the MD5 checksums for the plaintexts (all uppercase, no spaces or punctuation):

    0. da59d3c10bbb3420d4ac815d3cd47771
    1. e5fee55369cc88cd73183764038363c6
    2. 72aa17f23eb2bb3938bd44946ae01d6b
    3. bbbdf490dcdd6eae2fd2ecfa6ee4b895
    4. 8e2b9ed0c3e53e61ae11a9fd186f167b
    5. da67ed4324ff97ef018353764ee6dc23

    If you can solve #0, then you are doing great. If you can solve #1 you are very good. If you can solve #2, then
    you are highly skilled. If you can do #3, #4, and #5, then you are obviously cheating. Have fun!

    #83837
    PuttPutt86
    Participant

    [Editred by Harry: Thanks PuttPutt, the usual rules still apply. If anything in a message is encrypted we need to check it first, so do repost with he info as you suggest below. Great to have you back, Harry]


    @Harry
    , @Jodie & @Elves: The above message is encrypted using the cipher that madness used for his ciphertext #0 above. If you want me to send you the plaintext and key before you approve this message for the forum, just let me know. Looking forward to another great challenge with you all. Many thanks, PuttPutt

    #83840
    PuttPutt86
    Participant

    @madness

    #1 is making me quite ‘hot’ under the collar

    But I don’t even know where to start on #2!

    #83854
    PuttPutt86
    Participant

    @Harry: No problem, please see below.


    @Madness
    :

    GwkyynpYfjmcTiqcefajDekwwEgukcbijfJyuextnggshmxAuhifdGobnihkronYnpxgpmbeKgrqdkyPdevodiuuTiqoieaxuiyxWkhxnjdltcfneSmnxibwfaslQczzkvaankhwbDybhtkeDybwyeTsfeddoClpihbtelihpSmuudousAuftzmadaiOjqsdkBobzwpscczAophdytaTmajkkyFxnkhgkCpvqptyuldkbAuhiifdDlnwcbDxgiawshrnnXjbgjxuczuwtrFvxbsosamLzgpHirhkwJhckxzxthcszNtxgxkkphipqXjtucjqjKoqjdPmzeziuuhdeleLjnhgnnhgnn

    ——-

    @Harry
    , @Jodie &@Elves:

    [Decrypt and cipher info removed by the Elves]

    #83859
    madness
    Participant

    @PuttPutt86, thanks for the kind message. Nice to see you, too.

    2 through 5 are not easy unless you figure out how to cheat. Ha ha ha ha

    #83889
    BreakTheCipher
    Participant

    I’ve tried my best to make a brute force script for this. It’s so close but it seems to be missing just a few bits in the final decrypt. Not sure if it’s a bug in my decrypt function or if it needs better optimisation, but hopefully it will work for most Alberti cipher texts once I fix this.

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