Unencrypted Whistler Variant in the Wild

Antimalware researchers Marius Tivadar and Cristian Istrate are back with a small update from the labs, this time about the Whistler bootkit family.

Another version of Whistler was recently found, with low detection rates. Known Whistler variants had their components stored after the last partition on disk; they were encrypted with their corresponding LBA as key. In this new version, the original MBR is also stored after the last partition, but is not encrypted as in the previous versions, rather simply XORed. The rest of the components are not encrypted at all, as you can see from the image:





As per usual, the new variant is detected by all Bitdefender software, including the recently released Rootkit Remover.

About the author



Razvan Stoica is a journalist turned teacher turned publicist and technology evangelist. When Bitdefender isn't paying him to bring complex subjects to wide audiences, he enjoys writing fiction, skiing and biking. Razvan Stoica started off writing for a science monthly and was the chief editor of a science fiction magazine for a short while before moving on to the University of Medicine in Bucharest where he lectured on the English language. Recruited by Bitdefender in 2004 to add zest to the company's online presence, he has fulfilled a bevy of roles within the company since. In his current position, he is primarily responsible for the communications and community-building efforts of the Bitdefender research and technology development arm.