IBM has reported an increase in malware volume and sophistication,the rise of exploit leasing and a lower number of vulnerability disclosures versus the first half of 2006 as part of its security statistics report for the first half of 2007. So far for the year, the IBM Internet Security Systems (ISS) X-Force research and development team has identified and analysed more than 210,000 new malware samples, already exceeding the total number of malware samples observed over theentirety of 2006.
X-Force uncovers in the report that the "exploits as a service" industry continues to thrive in 2007. The 2006 X-Force report indicatedthat managed exploit providers had begun to purchase exploit code from the underground, encrypt it so that it could not be pirated, and then sell it for top dollar to spam distributors. In 2007, these exploit providers have added the new practice of "exploit leasing" to their repertoire. By leasing an exploit, attackers can now test exploitation techniques with a smaller initial investment, making this underground market an even more attractive option for malicious perpetrators.
According to the report, Trojans (seemingly legitimate files that are actually malware) comprise the most voluminous category of malware so far in 2007, accounting for 28 per cent of all malware, in contrast to 2006 when Downloaders was the most common category. A Downloader is a low-profile piece of malware that installs itself so that it can later download and install a more sophisticated malware agent.
"The X-Force security statistics report for 2006 predicted a continued rise in the sophistication of targeted, profit-motivated cyber attacks," said Kris Lamb, director of X-Force for IBM Internet Security Systems. "This directly correlates to the rise in popularity of Trojans that we are witnessing this year, as Trojans are often used by attackers to launch sustained, targeted attacks." The use of Web exploit obfuscation continues to rise in 2007 in an attempt to make it difficult for signature-based intrusion detection and prevention products to detect attacks. In 2006, X-Force data reported that approximately 50 per cent of Web sites hosting exploit material designed to infect browsers were obfuscating, or camouflaging, their attack. In the first half of 2007, that number reached 80 per cent.
Counter to historical trends, X-Force reports a slight decrease inthe overall number of vulnerabilities uncovered in the first half of2007 versus the first half of 2006. A total of 3,273 vulnerabilitieswere identified in the first half of this year, marking a decrease of 3.3 per cent compared to the first half of 2006. This is the first time that vulnerability disclosure numbers have decreased in the first half of the year in the history of the X-Force vulnerability database, which was developed in 1997. However, the percentage of high impact vulnerabilities has gone up since 2006 from 16 per cent to 21 per cent for the first half of 2007.
X-Force points to several trends to explain the decrease in vulnerability disclosures in the first half of 2007 versus the exponential vulnerability growth trends observed in previous years. First, as themonetisation of vulnerabilities and exploits has gained attention and maturation in the underground marketplace, a larger percentage of vulnerabilities are remaining undisclosed and are instead being used covertly for monetary and criminal gain.