Buffer overflow in event handler in Intel Active Management Technology in Intel Converged Security Manageability Engine Firmware 3.x, 4.x, 5.x, 6.x, 7.x, 8.x, 9.x, 10.x, and 11.x may allow an attacker to cause a denial of service via the same subnet.

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.