This script is Copyright (C) 2015 Tenable Network Security, Inc.
The remote FreeBSD host is missing a security-related update.
The Xen Project reports :
A buggy loop in Xen's compat_iret() function iterates the wrong way
around a 32-bit index. Any 32-bit PV guest kernel can trigger this
vulnerability by attempting a hypercall_iret with EFLAGS.VM set.
Given the use of __get/put_user(), and that the virtual addresses in
question are contained within the lower canonical half, the guest
cannot clobber any hypervisor data. Instead, Xen will take up to 2^33
pagefaults, in sequence, effectively hanging the host.
Malicious guest administrators can cause a denial of service affecting
the whole system.
See also :
Update the affected package.
Risk factor :
Medium / CVSS Base Score : 4.9