News

Sasser Enters Round 6 as Patch Tuesday Arrives

• By Scott Bekker
• May 11, 2004

Just as IT brushes itself off from the Sasser worm, it's that time again. Today is Microsoft's Patch Tuesday, that day once a month when Microsoft puts out all the security patches it's been working on.

Sasser is a worm built to exploit one of the 20 vulnerabilities Microsoft fixed on April 13, the last Patch Tuesday. Sasser took advantage of the LSASS Vulnerability that was fixed with the patches in security bulletin MS04-011.

Four versions of Sasser came out over the previous week. A German teenager arrested over the weekend is allegedly responsible for those, as well as some work on the NetSky virus. Microsoft is forking over $250,000 from its pool of reward money to thank informants. Although a Sasser.E variant appeared about two days after the arrest, authorities said that version was probably released by the teen just before his arrest.

PandaLabs discovered an F variant of Sasser on Tuesday, but the security company's experts believe a less savvy hacker probably wrote that version.

Microsoft officials said there were more than 1.5 million downloads of its Sasser cleaning tool. Several security experts have warned IT to brace for further worms exploiting the April 13 family of vulnerabilities, or even some sort of "super exploit" or blended threat that rolls together several exploits.

Even as the bad guys scramble to further abuse the April 13 patches, Microsoft is getting ready for its next round of patches. It's tempting to think that Microsoft cleared the decks on April 13, especially given that it had been aware of two of the vulnerabilities for more than six months. But that's not likely. Microsoft has been posting and e-mailing notices to encourage IT administrators to sign up for its monthly Webcast explaining the latest round of vulnerabilities.