Dutch researchers found a new vulnerability named "TLBleed" in Intel processors which have Hyper-threading enabled.
The vulnerability allows the extraction of crypto keys from other programs running on the same processor by exploiting the processor's translation lookaside buffer (TLB). According to all reports, for this vulnerability to be exploited, direct access to the vulnerable system is required. Access through a direct logon or malware. There are currently no reports of this vulnerability having been exploited in the wild.
At this point, Intel has no plans to release a fix for this vulnerability. To find assets on which this TLBleed vulnerability could potentially be exploited on, you can run this report. The report displays all assets which have Intel processors with more logical cores than physical cores (indicating the presence of Hyper-Threading).