Jan 2, 2011 20:30 GMT  ·  By

According to researchers from antivirus vendor Trend Micro, the most remarkable threat for last year was by far the Stuxnet industrial espionage worm, which managed to get ahead other more long-running threats.

Stuxnet was discovered this summer, but it is believed to have existed since mid-2009. It is widely considered in the malware research community as the most sophisticated computer threat created to date.

At the time of its discovery, Stuxnet exploited four previously unknown vulnerabilities in Windows, at a time when exploiting a single one is a big deal.

Also, its complex code base, which was built for sabotaging industrial control systems, in particular those in uranium enrichment plants, makes this threat a game changer.

The second piece of malware in Trend Micro's top for 2010 is the one used in Operation Aurora, a cyber attack that exploited a zero-day flaw in Internet Explorer 6.

The attack planted a trojan that stole intellectual property from Google and over 30 other large US companies.

The third most remarkable threat was deemed to be the ZeuS crimeware, an information stealing trojan commonly used by Internet fradusters.

Zeus was used by a large cyber criminal gang dismantled this year to compromise and steal millions from the bank accounts of US and UK companies.

The fourth piece of malware on the list is SpyEye, a different crimeware toolkit, which is believed to have merged with ZeuS recently.

The father of all social networking worms, Koobface, is fifth. This years-old threat has suffered some very interesting changes in 2010, including its expansion to Twitter.

Bredolab, a notorious botnet, whose main author is believed to have been arrested back in October, is viewed by Trend Micro researchers as the sixth most remarkable piece of malware.

The highly sophisticated TDSS rootkit, also known as Allurion, came in seventh, while Mebroot, a rootkit that installs a startup component for itself in the Master Boot Record (MBR), was selected to be eight.

FAKEAV, Trend Micro's malware family for all scareware applications, which are virtually everywhere on the Internet these days, occupies the ninth position in the top.

Finally, the last one the list is Boonana. This is a cross-platform trojan coded in Java, which targets both Windows and Mac operating systems.

Overall, 2010 has been a plentiful year as far as malware development is concerned and some pretty interesting developments were seen on the threat landscape. Some of these might event set the trends for 2011.