Citrix XenServer QEMU FDC Buffer Overflow RCE (CTX201078) (VENOM)

critical Nessus Plugin ID 83763
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The remote host is affected by a buffer overflow vulnerability.


The remote host is running a version of Citrix XenServer that is affected by a flaw in the Floppy Disk Controller (FDC) in the bundled QEMU software due to an overflow condition in hw/block/fdc.c when handling certain commands. An attacker, with access to an account on the guest operating system with privilege to access the FDC, can exploit this flaw to execute arbitrary code in the context of the hypervisor process on the host system.


Apply the relevant hotfix referenced in the vendor advisory.

See Also

Plugin Details

Severity: Critical

ID: 83763

File Name: citrix_xenserver_CTX201078.nasl

Version: 1.11

Type: local

Family: Misc.

Published: 5/21/2015

Updated: 7/6/2018

Dependencies: citrix_xenserver_version.nbin

Risk Information


Risk Factor: Critical

Score: 9.7


Risk Factor: High

Base Score: 7.7

Temporal Score: 6.4

Vector: AV:A/AC:L/Au:S/C:C/I:C/A:C

Temporal Vector: E:F/RL:OF/RC:C


Risk Factor: Critical

Base Score: 9

Temporal Score: 8.3

Vector: CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Temporal Vector: E:F/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:citrix:xenserver

Required KB Items: Host/XenServer/version, Host/local_checks_enabled

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/13/2015

Vulnerability Publication Date: 5/13/2015

Exploitable With

Core Impact

Reference Information

CVE: CVE-2015-3456

BID: 74640