An encrypted diary recently posted on Reddit looks easy to solve, but so far nobody has broken it.

On my last visit to the r/codes group at Reddit, I discovered not only two encrypted sucide notes (I blogged about them last week), but also an encrypted diary I had never seen before. Encrypted diaries are a frequent topic on this blog. My encrypted book list contains about two dozens of them. As good as all of them are completely solved.

 

The diary

Contrary to most other encrypted diaries I introduced on this blog, the one I disovered on Reddit seems to be quite recent – probably even from the year 2020.

Of course, it’s always an ethical question whether one should encourage the deciphering of an encrypted document that might contain private information about people who are still alive. In this particular case (the encrypted document has already been published and studied elsewhere) I decided for introducing the diary on my blog, but I promise that in case the solution is found I will remove it from the comment section if it contains critical information.

Here’s the scan of the diary that was posted by a user nicknamed 21719 on Reddit:

Source: Reddit

21719 wrote: “Recently found a diary and the whole diary is written like this. Can any help with this?”

To my regret, nothing is known about the background of this cryptogram. As the message contains a cleartext passage (“Jan-05-Sunday”) written in English, it seems likely that the plaintext is English, too.

 

Another page

Apparently, many Reddit users tried to break this cryptogram, but to no avail. Some complained that the excerpt posted was too short for detailed analysis and that more text from the diary would be helpful. So, 21719 additionally published the following scan of a whole page:

Source: Reddit

As already mentioned, virtually all encrypted diaries known in the crypto community have been deciphered. This is because diary authors usually prefer simple ciphers that allow for speedy encryption. The cipher used here doesn’t look especially complicated either. My first guess would be that the author has utilized a simple substitution (MASC), but apparently things are not this simple. On Reddit nobody has posted a solution yet.

Can my readers do better?


Further reading: How prisoner of war Donald Hill encrypted his diary

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Kommentare (4)

  1. #1 Thomas
    11. Februar 2020

    Any Welsh speaker here? What catches the eye are the words starting with double characters. There are Welsh words starting with double consonants (ll, dd, ff). But that’s a long shot.

  2. #2 Lance
    Grovetown
    11. Februar 2020

    According to the poster, 21719, the diary comes from Kerala, Indian, and the poster believes that if English is not used, the text may be Malayalam.

    In addition, a transcript was posted:

    FCCOIMK AECCDDK KDKKAA DJD KDSDK KMMHH 8:30 OKKHMI KAEI. HHDEG OD QEA. OMPD DMMHDG HDDEAMMKDE DDMEG LGLAFRE. DJD NIDDK NFDJ FIDEDHM KMMG NCFKKDDK NHHMK HF QKLA TFDM CCPIAA DJD IDJHM CDSDK NCFJAEC CNNH REHIBBDDC DJD QKLA TFDM GCCAE FCDH MMCDM OKFK CCFC COECCDD! DJD DAEC NDFK KDMK: CDSDK MMG REHIBBEGQH!

    HHD GDLLISCPBBK IMMC KDDK, HF NCBLEK DDKBBAMEG IGNHFADA DB HHD CCEDD. DAECMH IDJ GDLLIMCBCAEK? DAK NCFKDAL BCID-C NIDDK IDJC DB IGNHFACDA. DJGGM AECGG— IMMC NCFIRECPG HFNNCM BHMMG GEGN IMMCAE HDDECMMCMH. DDIAAEG IDJ DB IAEC IGNHFAIDA CCEDD. 1 ½ BHNNG CCPBBK IMME. DB QPDBCFC ILEAACMH IDJK. DB HFIBBCMEG IDJKDDEIMMCMH. HCAEFCBBEG GCCAEFHDDECM DB IDJK ILEAA CMH HFNCCM NIDDK OKKAMK NFLEDG MMG IDJHM NCFCPDG DDIDM QEA DB DAECCDD CFKKMC. IDJHM NCFCPCCD CCEDDIMMC CAE REKMNNH, DB DAEFKG IGNHFACDA CCPC BCFBCG IDJ REKMNNH LIGNMK CCPI AECGCLEC CCBIPCCM DB LCEIBHHNC, CAE BHDN CCPFBBEG. QEA DJD MMG NCFCPEG IDJHM. MMCCDM, HDJD CCFHHM NCFCPCCDHC? IDJ MMCCM CCFC DB? QEA IDJ REKFAECPAA HDD GIDMCDM DIBBEGQCCODDKMH DAECCDD CFKKMMC. CAEFCBBEG ILEAACMH IDJK DB, MHOK E CMHA. DAK BCFPG HDDEG DJD IDJHM NDFCP DM DIBBHMMCMH . . .

    Jan -05 – Sunday. :- DJD GLS CPCRE. DDIAA DCMMHDG CCPKDD DAEPDE DDK REDDMECAA BHHAE CDJK DD REHIRE DJGGB NHOCMMHHDD MMG NCFDJ.

  3. #3 Magnus Ekhall
    Borensberg
    11. Februar 2020

    I noticed this as well. I thought that perhaps every word was written backwards, but there are also examples of words that ends with double characters…

  4. #4 ShadowWolf
    A quick analysis
    12. Februar 2020

    The short text IC is 0.077. A bit high for English, but still relatively normal for a short text.

    The doubled letters may be nulls. The isolated double letter “word” either isn’t a word or it is a single letter with a null.

    There is about 20 unique symbols in the short text. The usual rare letters are probably not used.

    The writing is sloppy. The writer is probably not working from a substitution table and instead is working from memory. This is a common problem with hand written alternate symbol sets.

    Maybe find more after transcribing the larger page. Unfortunately the larger page is not scanned at a very high resolution and it will take a while.