The compromise of corporate websites with malicious code and browser exploits became the preferred method for distributing malware last year, according to the annual security report from IBM's ISS security tools division.
Cybercriminals are turning businesses against their own customers in the ongoing effort to steal data, the X-Force report warns. The prevalence of these drive-by download attacks is fuelled by application vulnerabilities and, worse still, flaws in custom applications.
During 2008, more than half (55 per cent) the 7,406 vulnerabilities tracked by ISS involved web applications. Three in four of these flaws lacked a patch, a factor which goes a long way towards explaining why attacks that result in the planting on malicious code on legitimate websites are such a problem.
Large scale, automated SQL injection vulnerabilities of this type grew by a factor of 30 between the middle and end of 2008, ISS reports. "The purpose of these automated attacks is to deceive and redirect web surfers to web browser exploit toolkits," explained Kris Lamb, senior operations manager of IBM ISS's X-Force security research team.
These browser-exploit toolkits are commonly used to download Trojans or botnet clients onto vulnerable Windows PCs, typically through the use of unpatched browser exploits. Almost half (46 per cent) of all malware tracked by IBM during 2008 was made up of Trojan horse programs targeting users of online games and online banking. The login credentials of either can be sold through the underground economy.
Browser exploits rule the roost, but hackers are also trying their hand at other tricks. Malicious files posing as movie player updates and booby-trapped documents were also popular.
Meanwhile, link spamming - posting messages promoting malvertised websites in the comment section of blogs and news-related websites - more than doubled during the second half of 2008.
China overtook the US as the worst offender of hosting malicious websites for the first time in 2008.
IBM's report suggests the half-life for bug fixes may be far longer than previously thought. More than half (53 per cent) of all vulnerabilities disclosed during 2008 lacked a vendor-supplied patch by the end of the year. Worse still, 46 per cent of vulnerabilities from 2006 and 44 per cent of bugs from 2007 were without an officially-supplied fix by the end of 2008, it reports.
The study calls for a rethink in how the severity of vulnerabilities is rated with a greater emphasis of their potential for money-making malfeasance, the primary motive for web attacks and cybercrime, rather than the more technical evaluation of the risk posed by security bugs, made through schemes such as the Common Vulnerability Scoring System (CVSS).
"CVSS provides an essential base that the security industry desperately needs to measure security threats," Lamb explained. "But we also realise that cybercriminals are motivated by money, and we need to fully consider how attackers balance the economic opportunity of a vulnerability against the costs of exploitation.
"If the security industry can better understand the motivations of computer criminals, it can do a better job of determining when emergency patching is most needed in the face of immediate threats. We can also be more precise about determining when widespread exploitation of a vulnerability will take a long time to emerge, and when it is unlikely to ever emerge.
IBM ISS's X-Force team of security researchers has been tracking and researching security vulnerabilities since 1997, cataloging 40,000 security flaws in the process. It reports that 2008 was its busiest ever year, with a 13.5 percent increase in vulnerabilities compared to 2007. The overall severity of security flaws also increased, with high and critical severity vulnerabilities up 15.3 per cent.
The study also looked at spam trends during 2008, marked by the shutdown of rogue ISP MCColo in November. The type and origin of junk mail messages, as well as their volume, was affected by the shutdown, the X-Force team notes. China leapfrogged the US to become the top spam sender directly after the shutdown before it was supplanted by Brazil by the end of the year.
The latest (2008) edition of the X-Force Trends and Risk report can be found here. ®