Intel Processors Indirect Target Selection Vulnerability Allowing Information Disclosure

A vulnerability allowing information disclosure has been identified in some Intel processors. This issue arises from the exposure of sensitive information in shared microarchitectural structures during transient execution. It may allow an authenticated user to access confidential data through local means. The vulnerability is present in various Intel processor families, including certain generations of Intel Core and Xeon processors.

Impact

Exploitation of this vulnerability could lead to unauthorized access to sensitive information from shared microarchitectural structures, potentially allowing an authenticated user to infer the contents of host memory, including memory assigned to other virtual guests.

Remediation

Intel has released microcode updates to address this vulnerability, available through the Intel Linux Processor Microcode Data Files on GitHub. For Intel SGX customers, a TCB recovery is planned. Consult your dom0 OS vendor or hardware vendor for updated microcode. Additionally, Xen requires changes to address this issue, which involve recompiling Xen using Return Thunks. Patches for this vulnerability are available for Xen 4.17.x, 4.18.x, 4.19.x, and 4.20.x.