ZDI-07-006: Citrix Metaframe Presentation Server Print Provider Buffer
January 24, 2007
-- CVE ID:
-- Affected Vendor:
-- Affected Products:
Citrix Presentation Server 4.0
Citrix MetaFrame Presentation Server 3.0
Citrix MetaFrame XP 1.0
-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability since July 7, 2005 by the pre-existing Digital
Vaccine protection filter ID 3583. For further product information
on the TippingPoint IPS:
-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
systems with vulnerable installations of Citrix Presentation Server,
Metaframe Presentation Server or MetaFrame XP. Authentication is not
required to exploit this vulnerability.
The specific flaw exists in a print provider installed by the
Presentation Server. The cpprov.dll library doesn't properly handle
certain invalid calls to the EnumPrintersW() and OpenPrinter()
functions. For example, passing a string of 130 or more characters in
the first argument to the OpenPrinter() function results in a
stack-based buffer overflow and can be leveraged to execute code in the
context of the Spooler service, which runs as the privileged LocalSystem
-- Vendor Response:
Citrix has issued an update to correct this vulnerability. More details
can be found at:
-- Disclosure Timeline:
2005.07.07 - Pre-exiting Digital Vaccine released to TippingPoint
2006.10.02 - Vulnerability reported to vendor
2007.01.24 - Coordinated public release of advisory
This vulnerability was discovered by an anonymous researcher.
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vulnerability are not exposed to any parties until an official vendor
patch is publicly available. Furthermore, with the altruistic aim of
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who have a vulnerability protection or mitigation product.