Malware adopts disguises in attempt to dupe IT defences

Sophos has revealed the most prevalent malware threats and email hoaxes causing problems for computer users around the world during February 2007.

The figures, compiled by Sophos’s global network of monitoring stations, show that the HckPk family has had the greatest impact on computer users this month, accounting for more than half of malware seen during February.

Hackers are increasingly using encryption and packer tools – such as those belonging to the HckPk family – to camouflage their malicious code. January’s hardest-hitting worm, Dorf, plus the prevalent Dref mass-mailing worms are just two examples of the malware currently being hidden within HckPk programs. Sophos has also found that cybercriminals are constantly modifying their HckPk disguises in an attempt to bypass IT defences.

The top ten list of malware threats in February 2007 reads as follows:



 1.    HckPk          50.3%

 2.    Netsky         15.1%

 3.    Mytob          12.5%

 4.    Zafi            4.8%

 5.    Sality          3.8%

 6.    MyDoom          3.0%

 7.    Bagle           2.4%

 8.    Clagger         1.4%

 9.    Nyxem           1.1%

10.    StraDl          1.0%



       Others          4.6%

“HckPk is a bit like Mr Potato Head – it uses disguises to bamboozle anti-virus protection into thinking the attachment is safe when, in reality, malicious code lies within,” said Carole Theriault, senior security consultant at Sophos. “Today’s most widespread threats, such as Dref and Dorf, use HckPk, so by blocking it, we zap the nasty threats lurking inside. Users need to check that their anti-virus protection can proactively detect against previously unseen malware, otherwise they could be next in a long line of victims.”

Sophos’s proactive Behavioral Genotype Protection technology identifies and blocks malicious programs before they are executed, ensuring that HckPk variants and other suspicious programs are stopped before they infiltrate corporate networks.

In February, Sophos found that 0.39% of emails were infected (one in 256). It identified 7,757 new threats during the month, bringing the total number of malware protected against to 222,713.

The top ten hoaxes and chain letters in February were as follows:



 1.    Hotmail hoax                     31.2%

 2.    Olympic torch                     9.6%

 3.    Budweiser frogs screensaver       3.8%

 4.    A virtual card for you            3.0%

 5.    Meninas da Playboy                2.5%

 6.    Bonsai kitten                     2.4%

 7.    Bill Gates fortune                1.7%

 8.    Justice for Jamie                 1.7%

 9.    MSN is closing down               1.6%

10.    Applebees Gift Certificate        1.3%



       Others                           41.2%