Xen: Privilege Escalation A vulnerability in Xen's bundled QEMU version might allow privilege escalation. xen 2017-03-28 2017-03-28 609120 local 4.7.1-r8 4.7.1-r8

Xen is a bare-metal hypervisor.

In CIRRUS_BLTMODE_MEMSYSSRC mode the bitblit copy routine cirrus_bitblt_cputovideo fails to check wethehr the specified memory region is safe.

A local attacker could potentially execute arbitrary code with privileges of Xen (QEMU) process on the host, gain privileges on the host system, or cause a Denial of Service condition.

Running guests in Paravirtualization (PV) mode, or running guests in Hardware-assisted virtualizion (HVM) utilizing stub domains mitigate the issue.

Running HVM guests with the device model in a stubdomain will mitigate the issue.

Changing the video card emulation to stdvga (stdvga=1, vga=”stdvga”, in the xl domain configuration) will avoid the vulnerability.

All Xen Tools users should upgrade to the latest version:

# emerge --sync # emerge --ask --oneshot --verbose ">=app-emulation/xen-tools-4.7.1-r8"
CVE-2017-2620 BlueKnight whissi