Password incorrect if typed to quickly

[3rdalbum]

It's not a security feature, that's ridiculous.

Either don't use caps lock to capitalise individual letters when touch-typing, or file a bug report with Xorg to maybe have the problem fixed in later versions of X.

[CharlesA]

No, I am being deadly serious. It is a security precaution, because a lot of bots are used nowadays to enter and configure code at speeds faster than the average human being. The computers at Canonical Ltd. can (probably) detect who is human and who is not by how fast the codes are entered. It is like the GUFW disabling to prevent hackers from getting onto the computer and altering the firewall settings.

Source please. That doesn't sound very likely.

[houseworkshy]

You could try opening a terminal and using sudo for something trivial, then sudo -k, then sudo something trivial etc etc. If you recorded your desktop whilst doing this repeatedly you'd end up with a video and timeline. Perhaps change your password before posting it. Be worth seeing. If it's not a feature maybe look at your short cut keys, could be that when typed slowly the keys are seen individually but when fast you are unwittingly using a key combination ( more than one being held down at the same time ) which your system is set to recognise.

[coffeecat]

Typed it in the text editor and if I type quickly, even if I press caps lock again to type lower case, the letters are printed in upper case. It seems like there's a delay when the caps lock is pressed and that i have to slow down so that lower case is activated.

This is your problem. It has been known about for years and is a "problem" with xorg. Nothing to do with Ubuntu and certainly not a security feature.

You've correctly identified the delay - when you press caps lock the second time, the character typed immediately after will render as a capital if you are typing too fast. I've seen people describe this as a bug, but I don't know whether there has been a bug report raised with xorg. I've also seen debates about whether it is appropriate to use caps-lock in situations like this, some fast touch typists saying it is more efficient than using shift, and others disagreeing. I have no view since I am not a touch typist, and have no view whether this is a bug or not, but I have a pragmatic suggestion. Since the bug/feature is unlikely to go away soon, and since it is entirely out of Canonical's control, use the shift key for caps when typing in your password.

[3rdalbum]

Bug was reported a while ago and there is a workaround : https://bugs.freedesktop.org/show_bug.cgi?id=27903

Basically, Xorg turns off Caps Lock when Caps Lock no longer registers as being "down" after being pressed the second time. Windows turns off Caps Lock when it registers the second press of the Caps Lock key.

[tubbygweilo]

Noticed this a while ago, good for stopping someone from attempting to use my long, strong & hard pass phrase but every now and again I have to slow down and move my lips as I type.

Just remember to keep your keyboard crud free as just a little something caught under a key can give the impression of a fully depressed key when the reverse may well be true often causing all sorts of pass phrase problems.