Experts at Sophos, a world leader in IT security and control, have warned of a widespread attempt to infect email users by sending them a warning about a bogus Microsoft security patch.
The emails, which have the subject line "Microsoft Security Bulletin MS07-0065" pretend to come from Microsoft, and claim that a zero-day vulnerability has been discovered in the Microsoft Outlook email program. They go on to warn recipients that "more than 100,000 machines" have been exploited via the vulnerability in order to promote medications such as Viagra and Cialis.
Users are encouraged by the email to download a patch which, it is claimed, will fix the problem and prevent them from becoming attacked by hackers.
However, clicking on the link contained inside the email does not take computer users to Microsoft's website but one of many compromised websites hosting a Trojan horse. Sophos proactively detects the Trojan, without requiring an update, using Behavioral Genotype® Protection as Mal/Behav-112.
The emails claim to come from Microsoft.
"Security bulletins from Microsoft describing vulnerabilities in their software are a common occurence, and so its not a surprise to see hackers adopting this kind of disguise in their attempt to infect Windows PCs," said Graham Cluley, senior technology consultant for Sophos. "The irony is that as awareness of computer security issues has risen, and the need for patching against vulnerabilities, so social engineering tricks which pose as critical software fixes are likely to succeed in conning the public."
In examples seen by Sophos experts, the emails have contained the recipient's full name, and the company they work for, in an attempt to lull users into a false sense of security.
"By using people's real names, the Microsoft logo, and legitimate-sounding wording, the hackers are attempting to fool more people into stepping blindly into their bear-trap," continued Cluley. "Users need to be on their guard against this kind of confidence trick or they risk handing over control of their PC to hackers with criminal intentions. They should also ensure that they are downloading Microsoft security updates from Microsoft itself, not from any other website."
Sophos recommends companies protect themselves with a consolidated solution which can defend against the threats of viruses, spyware, spam and hackers.