Many systems are still unprotected against the Conficker superworm, weeks after the malware began spreading across the internet creating a huge botnet of compromised machines thought to number in the millions.
Data from enterprise users of Sophos's Endpoint Assessment Test, which checks the state of Windows PC patching and anti-virus protection, suggest 11 per cent of users have failed to install the MS08-067 patch that guards against the vulnerability exploited by Conficker. The figures come from scans run since the start of the year.
Looking just at figures from March, when the countdown to the 1 April activation of one variant of Conficker generated worldwide headlines, found that 10 per cent were missing the essential patch, little changed on previous months. Exploiting the MS08-067 vulnerability in Server Services is one of the main vectors for the spread of Conficker.
Other infection methods include use of infected USB drives and spreading across local area networks by exploiting weak password shares.
April 1 passed off with nothing to report, but last week the massive botnet established by the Conficker worm began to stir, downloading a new component via P2P update functionality. Subsequent analysis has revealed that the latest variant (Conficker-E) is programmed to worked only up until 3 May. More significantly it downloads files associated with a rogue anti-malware application, called SpywareProtect2009, onto compromised Windows PCs.
If activated, SpywareProtect2009 invites prospective marks to pay $49.95 to "clean their machine". But the disinfection routines offered remove only fictitious threats, leaving the real malware on systems intact.
"The first version of Kido [Conficker], detected back in November 2008, also tried to download fake antivirus to the infected machine," net security researchers at Kaspersky Lab reports. "And once again, six months later, we’ve got unknown cybercriminals using the same trick."
The latest variant of the worm also attempts to download files associated with the Waledac botnet onto compromised PCs.
An overview of the malicious activities of the Conficker worm to date can be found on the Conficker Working Group website here. ®