My phone has been filling up with tweets from friends who got infected by this weekend's Twitter worms. Richard Clarke, the former president's cyberspace security advisor, is still trying to figure out how to stop the worm from sending out tweets in his name on his Blackberry PDA. He called me for help, and I in turn placed a call to Alan Paller, my good friend who is the director of research at the venerable SANS Institute.

Alan gave me some disturbing news. "If a vulnerable system has simply been left unpatched while [these new Twitter worms have] been circulating, the only real solution is to reformat the system's hard drive and reinstall all the software." That's the official advice from SANS. I returned Dick's call and told him the bad news. "The Clarke family isn't going to be very happy with this," he told me.

Dick asked me if he should reformat his wife's computer, as it didn't seem to be infected with the Twitter worms. "Is her system vulnerable?" I asked. He said, "yes." I asked, "has it been left unpatched so far?" He said, "yes." I said, "SANS is clear on this point. You need to reformat her hard disk. Alan said it is 'the only real solution.'"

Dick agreed that it would be best to follow SANS' advice. Last I heard, he said he was going to go looking for the CD-ROM that came with his Blackberry PDA. As for me, I'm still trying to hunt down some of my friends who are still sending out tweets...