It has been revealed that Intel's HT (hyperthreading technology) could be used by a malicious hacker to steal security keys using a sophisticated timing attack
. By taking advantage of the fact that HT processes share access to a chip's cache memory, a malicious user can determine the security keys to a particular computer by monitoring the cache for those keys. The flaw has been discovered by Colin Percival, an independent researcher, who found out about the problem while running the FreeBSD operating system. However, the problem is not solely present in FreeBSD, and apparently affects all HT aware operating systems.