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According to a new report out last week from McAfee Labs,
the rapid proliferation of malware has caused researchers to bump up their
estimates for cumulative the number of unique samples to float around the
Internet by the end of 2011. In its McAfee
Threats Report: Third Quarter 2011
, the firm reported that its increasing its estimated malware threat count from 70 million to 75 million.

Leading the growth curve this quarter was mobile malware,
which continues to pick up steam as smartphone adoption skyrockets,
particularly among Android devices.

"This has been a very steady quarter in terms of threats,
as both general and mobile malware are more prevalent than ever," said Vincent
Weafer, senior vice president of McAfee Labs. "So far this year, we’ve seen
many interesting yet challenging trends that are affecting the threat
landscape, including heightened levels of sophistication and high-profile
hacktivist attacks."

The report found that parasitic malware
exploits and exploit scripts in general are growing in favor with hackers over
threats like downloaders. Typically, these parasitic viruses and other file
infectors operate in memory and infect executables so that they’re started up each
time the executable is launched. According to the report, three of the top five
global threats in third quarter were parasitic or file-infector classes of
malware, behind only malicious iframes and malicious window shortcut files.

As for hacktivists, McAfee researchers said that attacks
were primarily perpetrated by members of the rogue group Anonymous in third
quarter, hitting organizations such as Arizona Fraternal Order of Police, Booz
Allen Hamilton, Bay Area Rapid Transit, Austrian Police and Goldman Sachs.

"These attacks were numerous but also confusing
because in many cases their goals were unclear," the report said. "At
the same time, on the same IRC channel, some called for increased protests
against PayPal, while others suggested opening PayPal accounts to receive
donations again. Some called for attacks on Facebook, while others created
pages to promote their opinions and operations."

On the malicious messaging front, McAfee delivered word
of a good news-maybe worse news scenario. Global spam levels continued to
decline last quarter and reached 2007 levels, but researchers found that
targeted spearphishing is stronger than ever.

"So, very much like malware, the noise tells us spam
levels have dropped, yet the signal we need to hear is that the bad guys have
changed their tactics," the report said. "They are protecting their
business models and are doing so with a sophistication that creates a more
dangerous threat than before."