Xen 4.x Vulnerability in FPU Handling on AMD64 Processors
CVE-2016-3159
3.8LOW
What is CVE-2016-3159?
The fpu_fxrstor function in Xen 4.x fails to correctly process writes to the hardware FSW.ES bit on AMD64 processors. This oversight enables local users within a guest OS to potentially access sensitive register content from other guests. By exploiting pending exception and mask bits, attackers can gain unauthorized insights, jeopardizing the confidentiality of information across different virtual environments. This vulnerability highlights significant flaws arising from unsuccessful attempts to rectify prior vulnerabilities.