Zombie PCs must die!

Comcast performs radical surgery on clueless users

Comcast, the US cable giant, is threatening to disconnect customers whose infected PCs are being used to relay spam messages.

Up to 30 per cent of spam is now spewing from hijacked "zombie" PCs. Spammers use Trojan horses and worms to take over PCs and use them as spam engines, a practice that can severely disrupt the operation of ISPs.

Recently, many Comcast customer IP addresses were recently blacklisted because of these spam-spewing zombies. The cableco has sent letters, warning customers who have been found with spam-sending PCs that they risk disconnection unless they clean up their act.

Comcast is adopting a line pioneered by Scandinavian ISP TeliaSonera. Last November, TeliaSonera said it would block Internet traffic to and from computers that send junk email or spam.

If other ISPs follow suit, this approach could make a big difference in cutting down on the crap flowing across the Net. Of course, ISPs should take care to correctly identify infected users and if they have any customer service ethos, offer assistance in cleaning up the PCs.

Comcast could have acted earlier to prevent itself becoming a major spam conduit, of course. Some of Comcast's other attempts to block spam have hit snags. A misapplied spam filter inadvertently stopped Comcast broadband punters from sending email to Russia for several days earlier this month, AP reports. ®

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