This website uses cookies to distinguish you from other users of our website. The use of cookies helps us to provide you with a specific service, to facilitate website use, to understand our visitors and to advertise to you. By continuing to browse the site you are giving consent to our use of cookies. Learn more in our Privacy Statement.

Security Services

Multiple Vendor AgentX++ Stack Buffer Overflow Vulnerability



Agent Extensibility (AgentX) Protocol was designed to address interoperability issues with extensible SNMP agents. AgentX++ is a C++ implementation of the AgentX protocol. It is one of several C++ based SNMP libraries developed by Frank Fock. For more information refer to the URLs below.


Remote exploitation of a stack-based buffer overflow vulnerability within AgentX++, as distributed with multiple vendors' products, allows attackers to execute arbitrary code with the privileges of the AgentX master process.

This vulnerability exists within the AgentX::receive_agentx function. By sending multiple blocks of data to the vulnerable function, an attacker could overwrite the data following the stack buffer, including the saved return address.


Exploitation allows an attacker to execute arbitrary code with the privileges of the running AgentX master process. In order to exploit this vulnerability, the attacker must be able to connect to the AgentX master port, usually TCP port 705. No authentication is required.

In the case of RealNetworks Helix Server v12, there is an option to install the AgentX master as an NT service. If installed in this way, the AgentX master will run with SYSTEM privileges. The privileges with which this process runs varies in other situations.

Although the issue is present in the Linux version of Helix Server v12, it is not exploitable due to stack buffer padding added by the GNU compiler. Reliable code execution has been confirmed on Windows targets.


iDefense confirmed the existence of this vulnerability in the following environments:

 RealNetworks Helix Server v12 on Linux RealNetworks Helix Server v12 on Windows 2003 SP2 AgentX++ source code v1.4.16 

All products utilizing the AgentX++ library are suspected to be vulnerable. Helix Server and Helix Mobile server versions prior to 14.0.0 are vulnerable (11.x,12.x and 13.x series).


iDefense is currently unaware of any workarounds for this issue.


RealNetworks Inc. has released a patch which addresses this issue. For more information, consult their advisory at the following URL.


The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2010-1318 to this issue. This is a candidate for inclusion in the CVE list (, which standardizes names for security problems.


11/03/2008 Initial Vendor Notification
01/14/2009 Initial Vendor Reply
04/15/2010 Coordinated Public Disclosure


This vulnerability was reported to iDefense by Manuel Santamarina Suarez.

Get paid for vulnerability research

Free tools, research and upcoming events


Copyright © 2010 Verisign, Inc.

Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customer service for permission.

Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.