Stupid XP trick - BIOS DOS?

["gregh" <chows () ozemail com au>]

Happened across this one quite by accident when my laptop CMOS battery died.

The date was set to 0/0/2003, something I cant MAKE it do but the CMOS
battery problem did anyway. If you can do that to your BIOS and you run
XPSP1 (may affect ALL Windows - I don't know), set it to that impossible
date and boot into Windows. You will find that your machine boots to the
spot where the pointer JUST appears and does nothing else. It doesn't lock
up, doesn't allow task manager or anything else, just loops in it's tracks.
Resetting the BIOS date to something within the normal calendar range then
allows it to boot normally, thereafter. This date trick may ALSO apply to
other dates outside the normal range such as 31st Feb and the 13th month too
so is worth thinking about.

Obviously, if someone writes a trojan/virus/mass mailing worm with this in
it to attack the BIOS date, it will stop XPSP1 all across the world,
possibly ANY Windows across the world. When you see it happen, it isn't
apparent what the hell is going on so the first thought is a Windows
problem. Anything you do from a boot disk or the XP CD other than set the
date to something valid will result in absolutely no change to your system.
So, if the trojan/virus/mass mailing worm was written so that it would be
the first thing to execute at every reboot, you would always end up with
this problem.

The fix? MS should write Windows to recognise an invalid date parameter and
to set the date to something valid and then let the user know in booting,
similar to what it does in Win98 when it changes to or from Daylight
Savings. Until XPSP1 can handle invalid date parameters, it is wide open to
the loss of millions of dollars across the world as it refuses to work.

Wonder how long it will take to write this?

Greg.


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