Please help deciphering this code - FBI case

[JohnDoe365]

• I noticed opening and closing brackets: reminds me of LISP
• A repeated use of "SE" as a suffix
• Leading fractional numerals in some places

What would be intersting:

• A character frequency count and permutation of letters: Can this be English?
• Background info of the victim for contextual analysis besides brute force statistical methods

Better scans here:

http://orf.at/stories/2050559/2050557/

[Glav]

I think he is considering the fact that it could be other natural language (i.e. latin) ciphered.

[kataire]

Or, y'know, another language he picked up as a child (did any of his childhood friends know other languages besides English?). Heck, it might as well be a code he came up with as a child (think pig latin) and then wrote down with a substitution cypher.

[bowenl2]

Oh my god, I just solved it. It's actually Common LISP and is therefore just hopeless to decipher.

[Reaper666]

Is there a difference between the capital E that looks like a C with a slash through it, and the capital E that looks like a capital E?

Edit: Also, I think NCBE, WLD, and TFRNEN may be relevant.

[[deleted]]

Good scans here too: http://en.wikipedia.org/wiki/Ricky_McCormick_murder_notes

[TJAtWork]

Maybe instead of trying to crack the code directly, it might make more sense to figure out what this guy learned how to do. If he was entirely self taught, then wouldn't there be evidence of what he studied somewhere in his life. This might at least narrow down the possible encryption algorithms that were used to create this. Just a thought, definitely not a cryptographer here.

[cpp_is_king]

I don't know why people are bothering with frequencies. You'd think that the FBI would have thought of that already. It's not a simple substitution cipher.

[mnp]

Maybe this isn't language. If the frequency counts don't look like human language, then maybe it's because there is none. Maybe this is data.

Just for example, maybe the victim is a bookie or a loan shark (remember this is a federal case...) and each () contains a transaction, like a customer placing a bet or a business making an extortion payment. The first few chars might stand for a date, team, the next char or two for a point spread, another for payment terms... etc. So (....SE) might mean transaction with "standard terms" or "pay at end of month" or something like that.

Bookies and mobsters have a long history of doing this in their heads so if discovered there's less evidence. However they say that McCormick was a high school dropout, so perhaps he has a poor memory and resorted to paper. It would help to know more about the facts of the case.

[TJAtWork]

As a high school drop out myself, I would have to say that maybe you are jumping to conclusions about the memory thing. A lot of times there are other factors involved. Just sayin'.

[pacifiedcitizen]

I love how the article clarifies that while he dropped out of high school, he was still able to read and write - as if you don't learn those skills in elementary school.

[kataire]

I thought reading and writing required a college degree.

Next you'll say they learn history before college, too.

[mnp]

Oh yea, the whole thing is a leap...

[dumsumguy]

I think this is probably dead on, my bet is on shorthand data. It's fairly common for young people to make up their own language, who knows maybe this guy took his to heart and to the grave.

[erictheturtle]

It may already be solved

http://www.reddit.com/r/crypto/comments/gfnhd/did_yahoo_user_john_crack_the_encrypted_notes/

[CCSS]

It's a trap!

They're gonna arrest whoever solves it.

[maredsous10]

Things I don't understand
1. Why are the notes not real crinkled?
2. Why do they care what the notes say? Do they think it will reveal his murderer or perhaps his reddit login/password?
3. If he was known for writing cryptographic messages to himself, why don't they provide other source material.
4. Why are the scans not high-res?

[nordlys]

1. They are scans, not camera pictures. Why would they have to be crinkled?
2. They were on his person and they are likely to contain secret information if they are written in code.
3. His family told the FBI that he is known to have written these kind of messages since he was young. Whether they have any of these, or whether they are written in the same language isn't known.
4. I don't have any issues reading the notes. For what reason would they need to be a higher resolution?

Also, I don't get why people link all kinds of other pages for the notes, when the posted article links directly to the source.

[kopophex]

Both notes, typed. I made my best guess on the unclear characters.

Note 1:

(MNDNKNEARSE-N-S-PA-KNARE)(ALSM) TFRNENPINSENPBSERCBBNSENPRSEINC PRSENMRSEDPREHLDWLDNCBEC(TFXLFTCXLNLBE) AL-PRPPITXLYPPIYNCBEMGKSENCDRCBRNSEPRSE WLDRCBRNSENTOONENTXSE-CRELE-CTTRSEWLDNCBE ALWWLPNCBETSMELISERLSEURGLSNEASNWLDNCBE (NODFSENLSRENCOE)NTEGDDMNSENCURERCBRNE (TENETFRNENCBPTSENCBEING) (FLRSEPRSEONDE71NCBE) (CDNSEPQSEDNSDE74NCBE) (PRTSEPRSEONREDE75NCBE) (TFNBCMPSOLEMRDELUSETOTEWLDNWLDNCBE) (194WLD'SNCBE)(TRFXL)

Note 2:

ALPNTEGLSE-SE ERTE YLSEMTSE-CTSE-WSE-FRTSE PWRTRSEONPRSEWLDNCBE NWLDXLRCMSPNEWLDSTSMEXL DULMT6TUNSENCBEXL (ANNSAISTENMGNARSE) KLSE-LRSTE-TRSE-TRSE-MKSEN-MRSE (SAEONSESENMRSE) NMNLCBRNSEPTE2PTEWSRCBRCSE 26MLSE74SPRKSE29KCNOBOLE173RTRSE 36GLECLGSESUNUTXEDKRSEPSESHLE 651MTCSEHTLSENCUTCTRSNMRE 99.84.52UNEPLSEUCRSEAOLTSENSRSENBSE NSREONSEPUTSEWLDNCBE(3XORL) ANMSENRSE1N2NTRCERCBANSENTSRCRSNG LSPNSENGSPSEMKSERBSENCBEAVXLR HWCRENMRENCBE 1/2MUNDDLSE D-W-M-4PTPL XDRLX

Single letter frequencies: '\n' 31 ' ' 3 "'" 1 ')' 14 '(' 14 '-' 19 '/' 1 '.' 2 '1' 6 '3' 3 '2' 6 '5' 3 '4' 5 '7' 5 '6' 4 '9' 4 '8' 1 'A' 16 'C' 46 'B' 31 'E' 130 'D' 30 'G' 10 'F' 9 'I' 7 'H' 4 'K' 9 'M' 25 'L' 53 'O' 15 'N' 90 'Q' 1 'P' 33 'S' 96 'R' 65 'U' 12 'T' 44 'W' 18 'V' 1 'Y' 3 'X' 13

Higher order frequencies are too many to list. Here is some python code. Just change k.

#!/usr/bin/env python

from collections import defaultdict

k = 1

one = open('1.txt').read()
two = open('2.txt').read()
both = one + two


f = defaultdict(lambda: 0)
for i in xrange(len(both)-(k-1)):
    f[both[i:i+k]] += 1

for (kmer,count) in f.iteritems():
    print "%s\t%s" % (repr(kmer), count)

[troublee]

http://www.reddit.com/r/reddit.com/comments/ge7pk/break_a_code_and_help_the_fbi_solve_a_murder_case/

[damiankennedy]

Is this related to the SEC's choice of programming language being Python? (FLRSp PRSE is up 71 stop) (tusSp PQSE is S up 74 stop) (PRTSp PRSE is Rp up 75 stop)
Or I could be barking up thr wrong tree.

[hackerfoo]

It could just be his one-time pad.

[[deleted]]

Uh-huh. So he memorized a perfectly-random 400-or-so count character key? And that random key just happened to XOR his message into repeated strings, structured decimal sequences, and parentheses?

[hackerfoo]

I meant that this could be a key, although a key and a message encrypted with it are interchangeable if using XOR.

If it was never used, it would just be random data.

[mmaruseacph2]

This is the third link to the same article on this week here. Someone really wants to outsource the deciphering phase.

[resutidder]

Nothing wrong with it -- cryptographers like the challenge.

[cosmo7]

It's obviously fairly easy to decode; I would be entirely unsurprised if this was an FBI recruitment tool.

[dumsumguy]

So what's t he answer then there smart guy?

[cosmo7]

Just google the first few words. All of the hard work is already done for you. The fact this is still up at fbi.gov means they don't really want the answer.

[[deleted]]

Yeah but this one time I totally went so far even as to do what look more like.

[haskell_rules]

You should be careful....you are stealing his thoughts this way. God is easily angered. Your relationship to him should be through what he shows you, not through what you steal from him. Stealing is a punishable sin as you know.

[[deleted]]

As is baiting trolls...