#2994 Improve clipboard security

[j0ka]

When the clipoard is used, Keepass copies the password to the clipboard, and clears the clipboard after some time. That way, another app can possibly steel the password from the clipboard.

However, it is possible, to announce a value to the clipboard, which is rendered at the moment, when it is pasted. Unless it is not pasted, it is not stored in the clipboard.

So a more secure method would be: Announce the password to the clipboard. Render it at paste-time and at the same time give some user-feedback (beep, sound, flashing button etc.), and then immediately clear the clipboard.

That way, it becomes really difficult to steal the password from clipboard. In case another app queries the clipboard after Keepass has announced its password, Keepass would beep before the user has pasted the value -> in that case, the user knows that something is wrong and can take appropriate actions. In case the other app waits until the user has pasted the password, it will find a cleared clipboard.

[Dominik Reichl]

KeePass had such an option, but it was removed in version 1.25 (in 2013) due to compatibility problems. For example, it turned out that there are applications that read the clipboard data multiple times during a paste operation and thus don't work properly when the clipboard is cleared immediately after the first read. Therefore, I'm not planning to implement such an option again.

Thanks and best regards,
Dominik