A security flaw within Intel Core and Xeon processors can be potentially exploited to swipe sensitive data from the chips’ math processing units. Malware or malicious logged-in users can attempt to leverage this design blunder to steal the inputs and results of computations performed in private by other software.
These numbers, held in FPU registers, could potentially be used to discern parts of cryptographic keys being used to secure data in the system. For example, Intel’s AES encryption and decryption instructions use FPU registers to hold keys.
In short, the security hole could be used to extract or guess at secret encryption keys within other programs, in certain circumstances, according to people familiar with the engineering mishap.
Modern versions of Linux – from kernel version 4.9, released in 2016, and later – and modern Windows, including Server 2016, as well as the latest spins of OpenBSD and DragonflyBSD are not affected by this flaw (CVE-2018-3665).
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