ZDI-11-023: Citrix Provisioning Services streamprocess.exe Remote Code Execution Vulnerability

https://www.zerodayinitiative.com/advisories/ZDI-11-023

January 20, 2011

-- CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/A:C)

-- Affected Vendors:
Citrix

-- Affected Products:
Citrix Citrix Provisioning Services

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10781.
For further product information on the TippingPoint IPS, visit:

    https://www.tippingpoint.com

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Citrix Provisioning Services. Authentication
is not required to exploit this vulnerability.

The specific flaw exists within the streamprocess.exe component which
listens by default on UDP port 6095. When handling a packet of type
0x40020010 the process blindly copies user supplied data into a fixed
length buffer on the stack. A remote attacker can exploit this
vulnerability to execute arbitrary code under the context of the SYSTEM
user.

-- Vendor Response:
Citrix has issued an update to correct this vulnerability. More
details can be found at:

https://support.citrix.com/article/CTX127149

-- Disclosure Timeline:
2010-06-09 - Vulnerability reported to vendor
2011-01-20 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * AbdulAziz Hariri

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