A hidden rootkit that reinstalls Trojan
Due Credit:
Techrepublic
A rootkit that hides from Windows on the hard drive's boot sector is infecting PCs say researchers.
The rootkit overwrites the hard drive's master boot record (MBR), the first sector -- sector 0 -- where code is stored to bootstrap the operating system after the computer's BIOS does its start-up checks.
According to other researchers, including those with the SANS Institute's Internet Storm Center,the rootkit has infected several thousand PCs since mid-December, and is used to cloak a follow-on bank account-stealing Trojan horse from detection as well as to reinstall the identity thief if a security scanner somehow sniffs it out.
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