A new side-channel attack takes advantage of the speculative execution feature in modern processors to recover data from users’ CPUs. Researchers named BranchScope because it attacks the “branch prediction”” operation. This is the same part of a CPU speculative execution process that the Spectre variant 2 (CVE-2017-5715) vulnerability also targets. The attack can be launched from user space (no admin rights) and has an error rate of less than 1%. There are no mitigations currently in place for BranchScope attacks
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