Windows 7: World's Most Sophisticated Rootkit Is Being Overhauled

Experts from security vendor ESET warn that TDL4, one of the most sophisticated pieces of malware in the world, is being rewritten and improved for increased resilience to antivirus detection.

"ESET researchers have been tracking the TDL4 botnet for a long time, and now we have noticed a new phase in its evolution," announced David Harley, the company's director of malware intelligence.



"Based on the analysis of its components we can say that some of those components have been rewritten from scratch (kernel-mode driver, user-mode payload) while some (specifically, some bootkit components) remain the same as in the previous versions," he noted.