a Few hours ago, May 21, 2018, Intel released a statement about: Details and Mitigation Information for Variant 4 This is relevant to consumers as this is the fourth variant of the “Spectre” family of security issues related to processors.
Intel states that: “This new derivative is called Variant 4, and it’s being disclosed jointly by GPZ and Microsoft’s Security Response Center (MSRC)”
According to Intel, the performance impact of mitigating this fourth variant could be almost 10% of CPU performance. (2-8% Intel states, based on their own general benchmark tests)
Variant 4 seems to be of specific importance to consumers as Intel has stated that researchers demonstrated variant 4 in a language-based runtime environment.
Technically this means that this 4th variant could theoretically be relevant to Javascript and could affect web browsers.
Read more about this on the Intel Website: https://newsroom.intel.com/editorials/addressing-new-research-for-side-channel-analysis/