ZDI-08-002: Citrix Presentation Server IMA Service Heap Overflow 
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-08-002.html
January 17, 2008

-- Affected Vendor:
Citrix

-- Affected Products:
Metaframe Presentation Server 3.0
Presentation Server 4.0, 4.5
Access Essentials 1.0, 1.5, 2.0
Desktop Server 1.0

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 5469. 
For further product information on the TippingPoint IPS:

    http://www.tippingpoint.com 

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

The specific flaw resides in the Independent Management Architecture
service, ImaSrv.exe, which listens by default on TCP port 2512 or 2513.
The process trusts a user-suppled value as a parameter to a memory
allocation. By supplying a specific value, an undersized heap buffer
may be allocated. Subsequently, an attacker can then overflow that heap
buffer by sending an overly large packet leading to arbitrary code
execution in the context of the SYSTEM user.


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

http://support.citrix.com/article/CTX114487

-- Disclosure Timeline:
2007.07.20 - Vulnerability reported to vendor
2008.01.17 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by Eric DETOISIEN.

-- About the Zero Day Initiative (ZDI):
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through the ZDI can find more information and sign-up at:

    http://www.zerodayinitiative.com

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