Editing 1286: Encryptic

Web sites and other computers that authenticate users via passwords need to be able to know if the user typed in the right password. But storing the password itself on the computer has been known to be unnecessarily risky since the publication of [http://www.neurosecurity.com/articles/security/passwd.pdf Password Security: A Case History] in 1978. In that paper, Robert Morris and Ken Thompson demonstrated the practice of using a slow, cryptographically-secure one-way {{w|hash function}}, so that even if the password file is stolen, it will be very hard to figure out what the passwords are, so long as the passwords themselves are suitably complex. They also pioneered the use of {{w|Salt (cryptography)|a "salt"}} which makes each password hash completely different even if two users use the same password. See [http://security.blogoverflow.com/2011/07/a-tour-of-password-questions-and-answers/ A tour of password questions and answers] for background on salts and suitably slow hash functions.

Adobe, however, ignored these well-known principles, and instead stored over a hundred million passwords in a reversibly encrypted way, using a terrible choice of encryption methods which exposes a great deal of information about the passwords, and does not involve a salt. This password database was recently obtained by someone and released on the Internet.

In particular, Adobe used {{w|Triple DES}}, an older encryption algorithm which can still be relatively secure when properly used, but they {{w|Electronic codebook|used it improperly}}. It works on 64-bit (8 character) blocks. Assuming that the passwords are stored in plain ASCII, this means that a sequence of 8 characters in a password which starts on a character position which is a multiple of eight is always encrypted to the same result. Therefore, two passwords starting with "12345678" would start with the same block after being encrypted. Furthermore, this means that you can actually get a very good idea of the length of the password since anything with only one block is a password with length between 1 and 8 characters, and having two blocks implies it has between 9 and 16 characters, etc.

Adobe also stored hints users created for their passwords. That means that an attacker knows not only if the same 8 characters are used for multiple passwords but also has some hints for guessing them. That means that common password portions should be easy to recover and that any user may be "compromised" by someone else using a part of the same password and providing a good hint. As an example, a password having three hints "Big Apple", "Twin Towers" and "If you can make it there" is probably "New York" or a simple variation on that. The weakness here is that no decryption and therefore no hard cracking has to take place, you just group the passwords by their encrypted blocks and try to solve them like a crossword puzzle. These weaknesses have already been used to presumably identify a password used by {{w|Edward Snowden}}, as discussed at [http://7habitsofhighlyeffectivehackers.blogspot.com/2013/11/can-someone-be-targeted-using-adobe.html 7 Habits of Highly Effective Hackers: Can someone be targeted using the Adobe breach?].

As mentioned on http://filosottile.github.io/analyzing-the-adobe-leaked-passwords/ the data in the comic isn't real and contains a hidden message. If the "user password" hashes are Base64 encoded, they read:

erAndyethereweareXOXOXOLetsLiveHereInThisTinySecretEncodedTextWorldForever==</pre>

More readable:

<pre>This was not a good use of your time

Lets Live Here In This Tiny Secret Encoded Text World Forever</pre>

E.g., with the initial unique hash blocks: <tt>python2 -c "print '4e18acc1ab27a2d6a0a2876eb1ea1fca'.decode('hex_codec').encode('base64')"</tt>

The last letter "r" is not fully encoded in the data shown, but any letter from "g" to "v" produces the same binary data.

 

 

 

===Passwords===

Note that characters in the passwords could be upper or lower case, and they may involve common substitutions like "0" (number zero) for "O" (letter O); therefore, the clues cannot guarantee that the answer shown here is precisely correct. Nevertheless, we have plenty of information for a brute force attack.

|<tt>[http://redwall.wikia.com/wiki/Matthias matthias]</tt>

|In ''{{w|Redwall}}'', several characters are associated with a sword hung from a weather vane, but only Matthias shares the name of an apostle (6 lines down).

|favorite of {{w|Apostle (Christian)|12 apostles}}

|<tt>{{w|Saint Matthias|matthias}}</tt>

|The hint suggests only 12 possibilities. Variant spellings, variant lists, and a replacement for Judas add to that number. But we already know which one by combining with the clue 6 lines up. (Surprise: it's the replacement!)

|This is a quotation from [http://www.biblestudytools.com/nrsa/judith/15-10.html Judith 15:10] in the Bible.

|<tt>{{w|Charlie Sheen|Charlie&nbsp;Sheen}}</tt>

|This refers to an episode of ''{{w|Two and a Half Men}}''.  Other answers are possible, but only this one fits the next line.

|<tt>{{w|Charlie X|Charlie&nbsp;X}}</tt>

|"{{w|Star Trek: The Original Series|TOS}}" refers to The Original Series (TOS) of ''{{w|Star Trek}}''.  Although this had dozens of episodes, only one fits the previous line as well as the next line.

|{{w|Sugar Land, Texas|Sugar Land}} is a suburb of {{w|Houston}}, {{w|Texas}}.  This fits with the previous line. {{w|Sugarland}} is a band, but it does not fit well with the previous hint, and would not lead to our first guess.

|{{w|Michael Jackson}} did many songs, but only one was {{w|ABC (The Jackson 5 song)|alphabetical}} (4 lines up).

|<tt>asdfghjkl</tt>

|<tt>asdfghjkl</tt>

|Probably a "keyboard mash" (e.g. asdfghjkl), a common password. The hint is a reference to the song "{{w|Monster Mash}}" ("He did the mash/He did the monster mash").

|<tt>asdfghjk</tt>

|A reference to the {{w|Edgar Allan Poe}} story "{{w|The Purloined Letter}}", this represents all the keys of the home row, or the keyboard mash password, but with one missing ("[[:wikt:purloin|purloin]]ed") letter.

|<tt>a8ae5745a2b7af7a&nbsp;9dca1d79d4dec6d5</tt>

|fav water-3 {{w|List_of_Pokémon|Pokemon}}

|<tt>[http://bulbapedia.bulbagarden.net/wiki/Tentacool_(Pok%C3%A9mon) Tentacool]</tt>

|This is the only [http://bulbapedia.bulbagarden.net/wiki/Water_3_%28Egg_Group%29 water-3] Pokémon with a 9 letter name ending in "l", so it must be this to fit with the password 'asdfghjkl'.

a8ae5745a2b7af7a 9dca1d79d4dec6d5  fav water-3 pokemon