When this happens, simply press Ctrl-V Ctrl-O Ctrl-M. Or alternatively, type "reset" and Return (Enter).
A terminal interpretes 0x0e byte as "activates the G1 character set", and 0x0f as "activates the G0 character set". The characters we read are in the G0 set. So, if there is no byte 0x0f after the last 0x0e in a binary file, everything will be shown in the unreadable G1 set, including the next shell prompt.
How does Ctrl-V Ctrl-O Ctrl-M work?
Ctrl-V is an 'escape character' - the next keystroke will always be interpreted as a literal character; Ctrl-O is 0x0f; Ctrl-M is carriage return. So the shell gets the command "\x0f" and outputs the error message "bash: \x0f: command not found". The byte 0x0f in this message turns the active character back to the readable G0.
G1 character set is not often used these days. Konsole chooses not to implement it at all, so we never have this problem in Konsole.