CVE-2017-2620: Citrix Xenserver

Critical severity, CVSS 9.9. EPSS: 3.6% chance of exploitation in the next 30 days.

Quick emulator (QEMU) before 2.8 built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to an out-of-bounds access issue. The issue could occur while copying VGA data in cirrus_bitblt_cputovideo. A privileged user inside guest could use this flaw to crash the QEMU process OR potentially execute arbitrary code on host with privileges of the QEMU process.

Affected products

• Citrix Xenserver: version 6.0.2 only; version 6.2.0 only; version 6.5 only; version 7.0 only; version 7.1 only
• Debian Debian Linux: version 7.0 only
• Qemu Qemu: before 2.8.0 (fixed in 2.8.0)
• Red Hat Enterprise Linux Desktop: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server: version 6.0 only; version 7.0 only
• Red Hat Enterprise Linux Server Aus: version 7.3 only; version 7.4 only
• Red Hat Enterprise Linux Server Eus: version 7.3 only; version 7.4 only; version 7.5 only
• Red Hat Enterprise Linux Workstation: version 6.0 only; version 7.0 only
• Red Hat Openstack: version 5.0 only; version 6.0 only; version 7.0 only; version 8 only; version 9 only; version 10 only
• Xen Xen: up to and including 4.7.1; version 4.7.1 only

Published 2018-07-27. Last modified 2026-06-17.