Operating systems on hardware platforms supporting simultaneous multi-threading (Hyper-Threading technology in particular) are potentially vulnerable to information leakage to local users. Proof of concept papers and code demonstrating successful attacks against cryptographic keys are in public circulation.
Hyper-Threading (HT) Technology allows two series of instructions to run simultaneously and independently on a single processor. With Hyper-Threading Technology enabled, the system treats a physical processor as two "logical" processors. Each logical processor is allocated a thread on which to work, as well as a share of execution resources such as cache memories, execution units, and buses.
Information could potentially be deduced by local users using programs capable of shared memory cache eviction analysis. Proof of concept code using timing and cache eviction analysis techniques have demonstrated that cyptographic keys can be deduced on Intel processors with Hyper-Threading technology (HTT) . It is likely that similar techniques could be employed on other processor architectures that support simultaneous multithreading.
Sensitive information, including cryptographic key material, may be leaked to other local users on the affected system.
We are not aware of an all encompassing short term solution to this issue.
Colin Percival is credited with bringing the issue to the attention of vendors and the wider community.
|Date First Published:||2005-05-23|
|Date Last Updated:||2005-08-05 20:29 UTC|