Talk:1700: New Bug

Explain xkcd: It's 'cause you're dumb.
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I'm new. For the explanation: A bug, as in a computer (programming) bug, can be reported and tracked, and many systems allow collaboration on the reporting and tracking of problems, or bugs, in code, and their solutions. Cueball reported a problem (bug) he found in the code, which presumably caused the server (program)—which he wrote as part of his project—to try to read the passwords as URLs before storing them. This exposes serious cross-site scripting attacks and other serious security vulnerabilities, and since handling password and user account information usually requires a lot of programming, this would be difficult to fix, which is why the character off-panel suggests burning the project down, as that would be much easier, and would solve any security problems, much more quickly than fixing the bug would. The comment text refers to Cueball's horrid solution to a horrid problem: Instead of solving the problem that is causing the server to read passwords as URLs, he can instead leverage a known problem in the programme which reads URLs which prevents it from reading a particular way of representing text in binary form, by adding a few characters to the user's password that the URL-reading program can't read. This would also "salt" the user's password, which is a security technique that makes passwords harder to figure out when they are stored properly. Cueball thinks this would solve the original problem, and two other problems at the same time, the second problem being the fact that user's passwords aren't salted (a security problem). The third solved problem is difficult to deduce.  Zyzygy 05:40, 29 June 2016 (UTC)

The third bug is the unicode handling, which would need to be solved in order to salt passwords with emoji since these are unicode only character. Although I'm not sure if salting with emoji really increases security since as a rule i'd say nobody uses emoji in their passwords. 162.158.85.123 06:34, 29 June 2016 (UTC)
Password:ย ๐Ÿ‘๐ŸŽ๐Ÿ”‹ฮ  141.101.98.131 10:11, 29 June 2016 (UTC)
That is a really funny password, but is it strong ennough? :-) --Kynde (talk) 20:22, 29 June 2016 (UTC)
Actually, nobody using emoji in their password would be reason salting with emoji is MORE effective. Salting doesn't really increase security of single password, but it does increase security of whole password database, because you can hash some string - like, 123456 and check whole database for users having that as password. If every password is salted with different emoji, this strategy will not work, because while you KNOW which emoji is used - the salt is stored unhashed with the password hash - it's always different so you need to compute new hash for every line in password database. Hashing takes MUCH more time than just comparing strings. And how it's even more effective? Because someone might actually get multiple databases and search for entries with same salt, hoping there will be enough of them to be worth it. And salt with emoji likely wouldn't be so common ... -- Hkmaly (talk) 09:54, 29 June 2016 (UTC)

From 108.162.221.22 (long rant)

Two comments: first, the explanation on password salting is incorrect. The current version says "Salting passwords increases security by adding random data to the passwords which primarily helps defend against dictionary attacks.". Password salting only protects against particular kinds of (common) attacks in specific situations. Most importantly, it is designed to protect passwords only in the event ofa database breach, when a malicious user has gained direct access to the database itself. Password salting provides no protection when brute force attacks (aka dictionary attacks) are directed at the application itself, as the application automatically takes hashes into account. Instead, proper password salting randomizes the hash for each password, ensuring that if two users have the same password, they will not have the same hash. This makes it much more difficult to guess passwords through attack vectors like lookup tables, reverse lookup tables, and rainbow tables. However, because the salt has to be stored with the password (otherwise the application would not be able to make sense of the hash itself), password salting does not secure passwords against dictionary attacks even in the event that a malicious user has managed to acquire the database itself. I will update the explanation with a brief description of what password salts do.
Finally, I think there is a big misunderstanding throughout this explanation. In a web services context the "server" (referenced in the comic) is a very different thing than the application that a programmer builds. A server can refer to either the computer itself or the software that is responsible for responding to web requests and executing the actual application. In a professional context, the application (which is what cueball would be building) would never be referred to as the "server". It is possible that this is a mis-use of terminology on the part of cueball or Randall, but I suspect that the term was used properly and intentionally. The reason is because if cueball's application is crashing the *server*, it takes the level of incompetence up to completely new (and unusual) levels, in much the same way that he has done in the past. Normally the programming language used to build the application, the software hosting the application, and the operating system itself have a number of safe guards in place to ensure that if an application misbehaves, the only thing that crashes is the application itself. For cueball's application to break through all those safeguards and crash the server itself (either the operating system or the web server software) would require cueball to have developed a program that operates *well* outside the bounds of normal procedures. Just for reference, as someone who has been building web software for over 15 years, I wouldn't even know where to start to crash the server from within an application. It would probably have to involve either exploiting a previously unknown bug in the programming language or some *very* poorly designed system calls. Special:Contributions/108.162.221.22 15:11, 29 June 2016โ€Ž 108.162.221.22 (Rememeber to sign your comments)

Regarding those last two points: sorry for my long unsigned rant. Didn't realize I wasn't logged in. Still haven't figured out how to sign comments. Gonna try it this time. Cmancone (talk) 16:51, 29 June 2016 (UTC)--

You made it ;-) --Kynde (talk) 20:22, 29 June 2016 (UTC)

Explanation says "There is no reason for password handling code to access urls" but that is somewhat wrong -- Password handling code frequently perform heuristics on the password to assess the strength, for example checking if part of the password is a dictionary word -- similar heuristics could be done to check thatthe password is not a URL, such as "xkcd.com" applying DNS and other internet resources as an extention of the concept of "dictionary". Spongebob (talk) 16:11, 29 June 2016 (UTC)

Currently the explanation says: "Finally, emoji will often include unicode characters, which means that, if one can effectively salt passwords with emoji, then the passwords should be able to be stored in unicode (although that *probably* doesn't require anything outside the Base Multilingual Plane, so that might not need full unicode support after-all)." I'm fairly convinced that this doesn't make sense and is incorrect. Regardless of what character encoding the password is in, hashing will convert the entire thing into binary. This binary is then typically stored as a base64-encoded string in the database. Ergo, it doesn't matter whether the original password strings were in unicode or not: they will be stored in the database as ascii (or binary), not unicode. I'm going to go ahead and remove this comment from the explanation. I'm pretty certain that there isn't enough information in the comic to figure out why salting passwords with emoji would fix a unicode-handling bug in the URL request library. So I suspect that there is no explanation there: either Cueball is entirely confused and his statement makes no sense, or there is simply not enough information given to help us understand why this solution might fix the problem. However, I'm not going to make any updates to the explanation about this yet, because perhaps I'm missing something someone else will notice. Cmancone 12:50, 29 June 2016 (ETC)

I suspect that the salting with emoji is to ensure that the password does not resolve as a URL (since the library cannot understand the encoding), and thus the issue of the crash is resolved, the issue of unsalted passwords is solved, and the issue of the unicode handling bug is "solved" by virtue of it now being a feature relied on by the system. 173.245.56.68 20:50, 29 June 2016 (UTC)

I removed from the explanation the discussion about how Cueball's system might be checking passwords to see if they are resolvable URLs as a check against weak passwords. The problem with this explanation is that if that is where the crash was happening, then salting the password with emoji would not fix the crash. For salting to fix the crash (as Cueball suggests it will) requires that the crash be happening during the hashing process, not during password validation. The reason is because password validation is performed on the original password itself, while only hashing happens on the salted password. So for salting to fix the crash it must be happening during hashing, not validation. If the bug is happening while checking passwords for strength then Cueball's suggestion of fixing it by adding in a salt will not actually fix the crash at all. It could be that Cueball is simply completely wrong about everything, but I think it makes more sense to go with an explanation where the title text didn't just get everything wrong.Cmancone (talk) 13:12, 30 June 2016 (UTC)

In the nomenclature I am familiar with mailto:[email protected] is a URL. If you accept that mailto (and other protocols) are also URLs some of the description is untrue. Fortunately the untrue bits are also unnecessary and can be deleted or generalized.--108.162.219.11 04:51, 1 July 2016 (UTC)