Multiple researchers have discovered vulnerabilities in the way the Intel processor designs have implemented speculative forwarding of data filled into temporary microarchitectural structures . This flaw could allow an attacker controlling an unprivileged process to read sensitive information, including from the kernel and all other processes running on the system or cross guest/host boundaries to read host memory. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details. To fully resolve these vulnerabilities it is also necessary to install updated CPU microcode. An updated intel-microcode package will be provided via a separate DSA. The updated CPU microcode may also be available as part of a system firmware update. In addition, this update includes a fix for a regression causing deadlocks inside the loopback driver, which was introduced by the update to 4.9.168 in the last Stretch point release.