I've mounted a cdrom device with
mount -o exec /dev/sr0 /media/cdrom0, since I couldn't execute files on it, when the drive was initially mounted by the virtual machine.
Now, when I run
cat /proc/mounts, I get the following output:
/dev/sr0 /media/cdrom0 iso9660 ro,relatime 0 0
It seems that the drive is still mounted read-only, but now I can execute files on it without errors.