Security experts Symantec warned that a new type of aggressive malware is threatening the network world as they prey upon social networks and mobile phone users.

In its July 2011 Symantec Intelligence Report, Symantec said that "polymorphic malware", or malware that is aggressive and rapidly changes, was seen in 23. 7 percent of e-mails identified as malicious. This figure is more than double seen six months ago, Symantec added, "indicating a much more aggressive strategy on the part of the cyber criminals responsible."

In July 2011, the global ratio of spam in e-mail traffic rose to 77.8 percent, indicating that one in 1.29 e-mails is a spam. This represents an increase of 4.9 percentage points compared with June 2011.

"The number of variants, or different strains of malware involved in each attack has grown dramatically, by a factor of 25 times, when compared to the previous six months. This is a disturbing proliferation in such a short time, increasing the risk profiles of many organisations as these new strains are much harder to detect using traditional security defences," said Paul Wood, senior intelligence analyst, Symantec.cloud.

The aggressive malware was frequently in attached ZIP files, and often disguised as a PDF file or an office productivity document.

A challenge

Symantec said the rise of such type of malware should concern businesses since traditional security measures simply won't do to stop this malware as this type of malware was designed to evade. Polymorphic malware uses many variations of the same code, but the function is basically the same. The aggressive nature of the malware makes it difficult for security experts to create counter measures to prevent such attacks.

For phishing attacks, the most common channels used were social networks and mobile phones, including wireless application protocol (WAP) pages, which are designed for mobile devices. Symantec said the motive for these targets on mobile devices is identity theft.

Symantec said the intended victims are lured to a fake login page to steal their information before they are redirected to the legitimate WAP pages.

Phishing activities in July increased by 0.01 percentage points since June 2011, with one in 319.3 e-mails (0.313 percent) comprising some form of phishing attack.

Geography

The July report also noted that Hong Kong was dethroned by Saudi Arabia to become the world's most spammed geography in the world. Saudi Arabia's' spam rate for the month was recorded at 85.6 percent while Hong Kong's rate was 76.8 per cent.

However, the month also saw a rise in the spam rate of Malaysia, at 77 percent, toppling Hong Kong as the most spammed in the Asia Pacific. The other most spammed countries in the Asia Pacific were Singapore, with a rate 75.7 percent; India, at 76 percent; and Japan, with a rate of 74.7 percent.

In Australia, phishing activity accounted for one in 850.8 e-mails and one in 2,503 in Hong Kong; for Japan, it was one in 13,167 and one in 872.9 for Singapore, the July report also noted.

In the July report, Symantec also listed best practice guidelines for enterprises, including monitoring network threats, and employing a comprehensive security solution and not just an anti-virus solution.