Josh Eads

A sequence of processor instructions can lead to unexpected behavior in some Intel processors, potentially allowing an authenticated user to enable escalation of privilege, information disclosure, or denial of service via local access. This issue is related to the interpretation of redundant prefixes and can cause the system to crash or become unresponsive. The vulnerability, termed Reptar, primarily affects multi-tenant virtualized environments where multiple virtual machines are run on the same host.

The issue concerns incorrect default permissions in some memory controller configurations for Intel(R) Xeon(R) Processors when using Intel(R) Software Guard Extensions. This may allow a privileged user to potentially enable escalation of privilege via local access. The vulnerability is related to Intel Microcode and is associated with default permission settings. Exploitation of the vulnerability could allow an attacker to access confidential data, compromise data integrity, and cause a denial of service.