On May 14, fixes for CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, and CVE-2019-11091 were released into the Ubuntu Xenial and Bionic kernels. These CVEs are security vulnerabilities caused by flaws in the design of speculative execution hardware in the computer's CPU. Researchers discovered that memory contents previously stored in microarchitectural buffers of an Intel CPU core may be visible to other processes running on the same core.
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