- Feb 7, 2014
- 1,540
- Content source
- http://www.kb.cert.org/vuls/id/960193
Overview
The AVG Secure Search toolbar, also known as AVG Safeguard includes an ActiveX control that provides a number of unsafe methods, which may allow a remote, unauthenticated attacker to execute arbitrary code with the privileges of the user.
AVG Secure Search is a toolbar add-on for web browsers that "... provides an additional security layer while searching and surfing to protect you from infected websites." One of the components provided by AVG Secure Search is an ActiveX control called ScriptHelperApi, which is provided by ScriptHelper.exe. This ActiveX control is marked as Safe for Scripting in Internet Explorer, which means that the author has determined that the control cannot berepurposed by an attacker. Because this control does not internally enforce any restrictions on which sites may invoke its methods, such as by using the SiteLock template, this means that any website can invoke the methods exposed by the ScriptHelper ActiveX control. The installer for AVG Secure Search also sets the ElevationPolicy registry value for the control, which means that the control is excluded from the Internet Explorer Protected Mode sandbox. The installer for AVG Secure Search also sets the Preapproved registry value, which bypasses the Internet Explorer ActiveX Opt-Infeature that was introduced with IE 7.
The AVG Safeguard and Secure Search ScriptHelper ActiveX control versions up to and including version 18.1.6 contain a number of unsafe methods that can be used in Internet Explorer. Other browsers do not appear to be affected.
Microsoft Support Document 240797. Alternatively, the following text can be saved as a .REG file and imported to set the kill bit for this control:
The AVG Secure Search toolbar, also known as AVG Safeguard includes an ActiveX control that provides a number of unsafe methods, which may allow a remote, unauthenticated attacker to execute arbitrary code with the privileges of the user.
AVG Secure Search is a toolbar add-on for web browsers that "... provides an additional security layer while searching and surfing to protect you from infected websites." One of the components provided by AVG Secure Search is an ActiveX control called ScriptHelperApi, which is provided by ScriptHelper.exe. This ActiveX control is marked as Safe for Scripting in Internet Explorer, which means that the author has determined that the control cannot berepurposed by an attacker. Because this control does not internally enforce any restrictions on which sites may invoke its methods, such as by using the SiteLock template, this means that any website can invoke the methods exposed by the ScriptHelper ActiveX control. The installer for AVG Secure Search also sets the ElevationPolicy registry value for the control, which means that the control is excluded from the Internet Explorer Protected Mode sandbox. The installer for AVG Secure Search also sets the Preapproved registry value, which bypasses the Internet Explorer ActiveX Opt-Infeature that was introduced with IE 7.
The AVG Safeguard and Secure Search ScriptHelper ActiveX control versions up to and including version 18.1.6 contain a number of unsafe methods that can be used in Internet Explorer. Other browsers do not appear to be affected.
Microsoft Support Document 240797. Alternatively, the following text can be saved as a .REG file and imported to set the kill bit for this control:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{F25AF245-4A81-40DC-92F9-E9021F207706}]
"Compatibility Flags"=dword:00000400
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Internet Explorer\ActiveX Compatibility\{F25AF245-4A81-40DC-92F9-E9021F207706}]
"Compatibility Flags"=dword:00000400
