Symantec Altiris ActiveX Buffer Overflow

November 12, 2009

A vulnerability has been reported in the Symantec Altiris Deployment Solution, which can be exploited by attackers to compromise a vulnerable system.

Symantec Altiris Deployment Solution software provides tools to deploy software on desktops and servers. It allows the management of drivers and software updates as well as provision for advanced automation and customized scripting for different deployment tasks.

Symantec Altiris Deployment Solution comes with an ActiveX control AeXNSConsoleUtilities.dll, which can be used to connect to the Deployment Server Web console. It can be instantiated in a web page using the OBJECT tag or via scripting. The ActiveX control has several methods which offer different functionalities. One of the methods is BrowseAndSaveFile, prototyped:

void BrowseAndSaveFile(BSTR bstrFileContent, BSTR bstrName, BSTR bstrTitle, BSTR bstrFilter, VARIANT varRoot)

A stack-based buffer overflow vulnerability exists in the AeXNSConsoleUtilities.dll ActiveX control, specifically, in the BrowseAndSaveFile method. The method does not properly validate the length of the bstrName argument before performing a string copy operation into a fix-sized buffer. An remote attacker can exploit this vulnerability by enticing a target user to open a specially crafted HTML document, which contains an overly long bstrName argument passed to the BrowseAndSaveFile method. Successful exploitation would overwrite critical stack data, such as return addresses and exception handlers, which leads to arbitrary code injection and execution with the privileges of the target user. In the case code execution is not successful, the vulnerable process may terminate abnormally causing a denial of service condition.

The vunerability has be assigned as CVE-2009-3031. It affects AeXNSConsoleUtilities.dll version, Symantec Altiris Deployment Solution 6.9.x, Symantec Altiris Notification Server 6.0.x, and Symantec Management Platform 7.0.x.

The vulnerable control is not intended to be called externally, therefore an invocation of the BrowseAndSaveFile method on the related ActiveX object is likely an attack. SonicWALL has released an IPS signature to detect and block specific exploitation attempts targeting this vulnerability. The signature is listed below:

  • 3201 Symantec AeXNSConsoleUtilities BrowseAndSaveFile Invocation