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My password is not accepted because it is too long

In password security, the longer the better. With a password manager, using more than 24 characters is simple. Unless, of course, the secure password is not accepted due to its length. (In this case, through STOVE.)

Possibly indicating cleartext storage of a limited field (which is an absolute no-go), or suboptimal or lacking security practices.

276 comments
  • Then again, there's not much point to super long passwords. They'll be turned into hashes, commonly of 128, 196, or 256 bits length. When brute forcing, by a certain length, it's pretty much guaranteed there's a shorter combination computing to the same hash. And an attacker doesn't need your password, just some password that computes to the same hash. With 256 bit hashes a password with 1000 characters isn't more secure than one with 15 in any meaningful way.

  • At one point years ago my work finally caught up with the 21st century and allowed creation of passwords longer than the fixed 8 characters it had always been. So I said great, made up something that was around 12 or so that I could remember. Until I logged into some terminal legacy programs we were still using and wouldn't take that length. So yeah, I went back to 8 characters that wouldn't break things. They eventually migrated away from such old programs and longer passwords became mandatory since they'd work everywhere, but I thought it was funny that briefly I tried to do the right thing but IT hadn't thought out the whole picture yet.

  • I had this problem with a fucking bank once. Even better are the sites that silently chop off characters after the internal limit, on the backend, but don't tell you or limit the characters on the frontend. I had a really fun time with that last scenario once, resetting my password over and over and having it never work until I decided to just try a shorter password.

  • YES, it pisses me off so much. Though I do kind see for some things having some upper limit of 256 for certain services. But I may be wrong in thinking that.

    For example I want a secure bank password but I only need it so long. Mainly because unlike my E2EE service if they are servered a warrant or hacked through another service all my data is there. Basically I can only do so much.

  • Hey at least it told you there maximum length, i signed up paramount+ last night and it only said 42 characters was too long.

  • It can also be just a randomly chosen limit. I work as a software engineer on a custom management software for a big client. For whatever reason until recently, the limit for email addresses in the master data was 50 character. Why? No clue but someone had decided that randomly in the past. Now it was increased to 100. Why again? According to RFC 5321 a limit of 254 would be the most sensible one. But the people who come up with those requirements just don't care. They decided it to be 100 from now on for no apparent reason.

    Then we have many input fields, that have a limit of 255 character. Why not 256? Why such a weird number in general? The people who use this software in production are most likely not the ones who usually think in powers of two. So why not make it 250 or 300 oder whatever?

    Sometimes those limits are just arbitrary with no technical or logical reason to back them up. Which doesn't make it less stupid mind you.

    • a limit of 255 character. Why not 256? Why such a weird number in general?

      255 chars + '\0' = 256

      Not weird at all.

      • I see your point, but we have Java backends and strings there are not null terminated. Also I'm very sure that those would never be the reason for our Postgres server to run out of storage so I don't get it why not make it more user friendly. We're not implenting an embedded system where every byte of storage counts.

276 comments