A vulnerability was reported in Xen. A local user on the guest system can obtain potentially sensitive information on the host system.
A local user on the guest system can exploit a flaw in the CMPXCHG16B emulation and resize a operand to obtain a small portion of data from the hypervisor stack.
x86 systems are affected.
ARM systems are not affected.
All HVM guest user processes, including unprivileged processes, can exploit this flaw on versions 4.6 and prior.