Maurycy Prodeus found a problem in cons.saver, a
screensaver for the console that is included in the mc package. cons.saver does
not check if it is started with a valid stdout, which combined with a bug in
its check to see if its argument is a tty (it forgot to close the
file-descriptor after opening the supposed tty) causes it to write a NUL
character to the file given as its parameter. This has been fixed in version
4.5.42-11.