Register - Login
Views: 99803152
Main - Memberlist - Active users - Calendar - Wiki - IRC Chat - Online users
Ranks - Rules/FAQ - Stats - Latest Posts - Color Chart - Smilies
05-03-22 07:17:48 AM
Jul - Craziness Domain - Decrypt this New poll - New thread - New reply
Next newer thread | Next older thread
Katelynn
480
woah I have a custom title field what
Level: 47


Posts: 277/483
EXP: 733601
For next: 32602

Since: 04-05-09

From: The dark and evil depths of western New York

Since last post: 8.9 years
Last activity: 8.6 years

Posted on 05-28-11 10:16:39 PM (last edited by Katelynn at 05-28-11 07:27 PM) Link | Quote
Over the past few months, I've been taking some weekend classes in digital security, which will ultimately lead up to OMG BIGGER SECRET THINGS. We have an assignment that will lead into our next chapter: create an encryption method. He didn't say how complex or simple, just to get it done by the next weekend.

So, I think I've got something. It's admittedly probably very easy to crack as I've only worked on it for about an hour (20 of those minutes being spent to program a quick encrypter and decrypter program pair).

Assuming no hints, as honestly your "enemy" will not know what to expect in terms of which encryption method is being used, I want to see if anyone can solve this:

0Y02X14201V1X481XU04W0W11X0VY08W2Z70V4U14Y120W03420V34W1781XU0Y1X4W02Y12XU0W180VW00X4W170V31W1Y044550VY1W18W00X00Z8W06W17812

That is the code to crack. You have until June 4th, 12:00 AM EST to crack it. Good luck.

Edit: Ah, yes. After the week is up, I'm afraid I won't be able to give the answer out if the teacher of the class determines that I've made the best encryption method out of the rest of the class. He said he'll use the best method for something, so if I give out the answer, eventually it could be reverse engineered a lot easier than if it's just left to sit.
Edit2: Blast, I can't disable my layout even with killing off the header/signature
ParaLax
510
Level: 47


Posts: 242/513
EXP: 735102
For next: 31101

Since: 05-18-11


Since last post: 9.9 years
Last activity: 8.2 years

Posted on 05-29-11 12:46:22 AM Link | Quote
I'm up to a challenge, I'll try, but I'll probably won't get it, but seeing as I have some time I might have a shot. I've done a few cryptograms in the newspaper, but not too much before.
devin

Yoshi
i'm mima irl
Level: 112


Posts: 2143/3519
EXP: 14931966
For next: 406239

Since: 04-29-08

Pronouns: any
From: FL

Since last post: 306 days
Last activity: 3 days

Posted on 05-29-11 12:57:18 AM Link | Quote
Only one cipher text? Come on, even the Bombe engineers had way more to work with than that

____________________

Photo by Luc Viatour
ParaLax
510
Level: 47


Posts: 247/513
EXP: 735102
For next: 31101

Since: 05-18-11


Since last post: 9.9 years
Last activity: 8.2 years

Posted on 05-29-11 01:08:45 AM Link | Quote
Originally posted by Cool Timpani
Only one cipher text? Come on, even the Bombe engineers had way more to work with than that


Yeah, it is a bit hard working with only that. Especially when in reality it can be in any language, it can have a space/not have a space and a number of things that make only that line pretty hard to crack.
Rick
M'Lord, there's a knife in your head!
Level: 152


Posts: 4260/7540
EXP: 43721884
For next: 579776

Since: 02-15-10

From: Maine

Since last post: 6 days
Last activity: 6 days

Posted on 05-29-11 01:43:39 AM Link | Quote
Jul loves to play Tetris.

____________________
Joe
Common spammer
🍬
Level: 111


Posts: 2092/3392
EXP: 14501174
For next: 367186

Since: 08-02-07

From: Pororoca

Since last post: 12 days
Last activity: 8 hours

Posted on 05-29-11 02:03:23 AM Link | Quote
Hmm, there's only 15 different characters in that encrypted string. Since the "6" character only shows up once, it's possible this example encrypted string doesn't cover the full alphabet. Assuming an alphabet of 16 characters, the ability to process arbitrary binary data, and no compression, your method expands data by at least 200% and the decrypted data is no more than 62 bytes long.

I think that's about all I can figure out about it.

____________________
Katelynn
480
woah I have a custom title field what
Level: 47


Posts: 278/483
EXP: 733601
For next: 32602

Since: 04-05-09

From: The dark and evil depths of western New York

Since last post: 8.9 years
Last activity: 8.6 years

Posted on 05-29-11 04:29:42 AM Link | Quote
Originally posted by Joe
Hmm, there's only 15 different characters in that encrypted string. Since the "6" character only shows up once, it's possible this example encrypted string doesn't cover the full alphabet. Assuming an alphabet of 16 characters, the ability to process arbitrary binary data, and no compression, your method expands data by at least 200% and the decrypted data is no more than 62 bytes long.

I think that's about all I can figure out about it.

The decrypted data is actually more than 62 bytes long, no compression methods used. Anyways, some hints as a guy on another board actually works with this kind of stuff and told me it's impossible to crack without something to go on. Whether he's lying about that, I dunno.

The end result will be in English using a roman alphabet. There's a typo in the unencrypted text since I'm retarded.
There is no punctuation or special ascii characters involved.
It's split into 5 parts. If you can find one part and figure that out, the rest should fall into line shortly.

____________________
╕..Х 'ии)) -:ж:-
╕.Х' .Х'ии)) Katelynn -:ж:-
((╕╕.Х' д д -:ж:-
(п`Х.Х┤п) (п`Х.Х┤п)
*`Х.╕(п`Х.Х┤п)╕.Х┤
д д`Х.╕.Х┤ д д





Lewis: Ok, we need to gain the trust of some villagers.
TotalBiscuit: I think Simon's qualified to do that!
*Simon approaches a villager and summons a swarm of angry bees*
Simon: Hello! Do you like bees!?
*The villager drops dead from the bees*
Simon: Oh dear... Um, that could have gone better...
Lyskar
12210
-The Chaos within trumps the Chaos without-
Level: 192


Posts: 9152/12211
EXP: 99321218
For next: 552353

Since: 07-03-07

From: 52-2-88-7

Since last post: 7.4 years
Last activity: 7.3 years

Posted on 05-29-11 05:59:29 AM Link | Quote
Stats
Time/Date
05-28-11 11:59:29 PM
Posts
9152
Days Here
1425
Level
140
Metal_Man88's Post
I know a bit about encryption but I'm not going to expect much out of my attempt, as I mostly only know how to encode ASCII things/data, and haven't spent any time encrypting things that aren't done for me by commercial software.

____________________

Eisnaught - SSQ² - Mobius Roleplay - SSS
Joe
Common spammer
🍬
Level: 111


Posts: 2093/3392
EXP: 14501174
For next: 367186

Since: 08-02-07

From: Pororoca

Since last post: 12 days
Last activity: 8 hours

Posted on 05-29-11 06:14:20 AM Link | Quote
Originally posted by Katelynn
The decrypted data is actually more than 62 bytes long, no compression methods used.
So, this means your encryption only allows certain characters, and the output length can always be predicted based only on the input length, correct?

I wonder if spaces count as punctuation.

____________________
Katelynn
480
woah I have a custom title field what
Level: 47


Posts: 280/483
EXP: 733601
For next: 32602

Since: 04-05-09

From: The dark and evil depths of western New York

Since last post: 8.9 years
Last activity: 8.6 years

Posted on 06-04-11 04:04:00 PM (last edited by Katelynn at 06-04-11 01:05 PM) Link | Quote
Ok, so time has passed. My encryption didn't exactly make it to the top, as the class teacher that this is for melted through it like butter, cracking it in 2 minutes. As such, I'm at liberty to share it :V

The base string was "whoever can decode this probably isnt a genius simply because i spent so little effort int making this encryption method". Yes, there was a typo.

Step 1: Take your string and separate every character, replacing them as follows: a = 0, b = 1 ... j = 9, k = 0A, l = B0, m = 0C, etc. Follow up until you reach F0. After that, q = 1A, r = B1, etc. Do this for every character, then recombine the entire string, ignoring the spaces in the source string. Or, for the lazy, just run it through the encrypter I programmed (to be released sometime in the next 1000 years when I stop being lazy)
Step 2: You take the end result after running it through the encrypter and separate the string into 32 byte long strings. The last one will likely not be 32 bytes long.
Step 3: The last sequence is then tossed into the middle of the encrypted string, separating the other 32 byte sequences. Those sequences are then swapped, so sequence A is now where sequence B should be and vice versa.
Step 4: Number the subsequences in A and B, then flip those around in reverse.
Step 5: combine and replace all instances of A within the string with Z, B with Y, etc. And there you have it.

This doesn't take into account numbers, punctuation, symbols or capital letters in the source string. My teacher said that it wasn't the best, but that I was in the top 5 in the class. It kinda scares me that I've surpassed people who claim to have a background in computer security, and these people are hoping to take this class and their experience into government jobs at the NSA, CIA and so on.

____________________
╕..Х 'ии)) -:ж:-
╕.Х' .Х'ии)) Katelynn -:ж:-
((╕╕.Х' д д -:ж:-
(п`Х.Х┤п) (п`Х.Х┤п)
*`Х.╕(п`Х.Х┤п)╕.Х┤
д д`Х.╕.Х┤ д д





Lewis: Ok, we need to gain the trust of some villagers.
TotalBiscuit: I think Simon's qualified to do that!
*Simon approaches a villager and summons a swarm of angry bees*
Simon: Hello! Do you like bees!?
*The villager drops dead from the bees*
Simon: Oh dear... Um, that could have gone better...
Joe
Common spammer
🍬
Level: 111


Posts: 2105/3392
EXP: 14501174
For next: 367186

Since: 08-02-07

From: Pororoca

Since last post: 12 days
Last activity: 8 hours

Posted on 06-04-11 07:38:57 PM Link | Quote
Originally posted by Katelynn
a = 0, b = 1 ... j = 9, k = 0A, l = B0, m = 0C, [...] q = 1A, r = B1, etc.
You said there was no compression. A string of ten "a" encrypts smaller than a string of ten "z". That's compression.

Seriously though, if your teacher cracked it in two minutes and it's in the top five of the class, your classmates are not very imaginative. (I would do something involving lots of bit fiddling and a pseudorandom number generator, and include a password system if that was allowed for that assignment.)

____________________
paulguy

Green Birdo
Level: 93


Posts: 1558/2294
EXP: 8032374
For next: 20436

Since: 09-14-07

From: Buffalo, NY

Since last post: 9.7 years
Last activity: 9.7 years

Posted on 06-04-11 07:59:27 PM Link | Quote
Paulguy's Post configuration
Yeah, most good encryptions use a lot of bit fiddling, without some kind of password or key, though, it's not very secure.

____________________
Next newer thread | Next older thread
Jul - Craziness Domain - Decrypt this New poll - New thread - New reply


Rusted Logic

Acmlmboard - commit 47be4dc [2021-08-23]
©2000-2022 Acmlm, Xkeeper, Kaito Sinclaire, et al.

30 database queries, 2 query cache hits.
Query execution time: 0.097574 seconds
Script execution time: 0.028033 seconds
Total render time: 0.125607 seconds