A flaw was found in computer hardware of the Intel microprocessors related to the instruction-side TLB (Translation Lookaside Buffer) that caches translations from guest (and host) virtual addresses into physical addresses.
This is a software fix that attempts to prevent exploitation of the hardware through preventing a hacker from creating an exploitable condition
Additional information:
https://access.redhat.com/security/vulnerabilities/ifu-page-mce
An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of instructions past bounds check.
It relies on the presence of a precisely-defined instruction sequence in the privileged code and the fact that memory writes occur to an address which depends on the untrusted value. Such writes cause an update into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire).
As a result, an unprivileged attacker could use this flaw to influence speculative execution and/or read privileged memory by conducting targeted cache side-channel attacks.
A race condition in specific microprocessors using Intel (R) DDIO cache allocation and RDMA may allow an authenticated user to potentially enable partial information disclosure via adjacent access.
Insufficient memory protection in Intel(R) TXT for certain Intel(R) Core Processors and Intel(R) Xeon(R) Processors may allow a privileged user to potentially enable escalation of privilege via local access.
Improper data forwarding in some data cache for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access. The list of affected products is provided in intel-sa-00330: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00330.html
Load value injection in some Intel(R) Processors utilizing speculative execution may allow an authenticated user to potentially enable information disclosure via a side channel with local access. The list of affected products is provided in intel-sa-00334: https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00334.html