Software Engineering Institute

Web browser plugins that allow remote web sites to reference content that resides on the local filesystem may be vulnerable to cross-domain security violations. In a typical attack scenario, an attacker must first place content in a known or predictable location on a computer. If a web browser plugin allows a remote web site to reference that content, this may allow attacker-supplied script to run within the security context of the local machine.

The Apple QuickTime plugin running in Microsoft Internet Explorer or Apple Safari fails to restrict web sites from accessing content on the local filesystem. Current proof-of-concept exploit code uses the HREFTrack attribute to exploit a cross-site scripting vulnerability in a file on Windows systems.

A remote, unauthenticated attacker may be able to execute script within the security context of the local machine. Script that executes within this context may be able to perform privileged actions, such as reading files from the local filesystem. These actions would not be possible by using script that executes within the security context of the remote web site.

Upgrade
This issue is addressed in Apple QuickTime 7.1.5 security document 305149. An update for Microsoft Windows is available on Apple Downloads and via Software Update.

Disable the QuickTime ActiveX controls in Internet Explorer

The vulnerable QuickTime ActiveX controls can be disabled in Internet Explorer by setting the kill bit for the following CLSIDs:

{02BF25D5-8C17-4B23-BC80-D3488ABDDC6B}
{4063BE15-3B08-470D-A0D5-B37161CFFD69}
More information about how to set the kill bit is available in Microsoft Support Document 240797. Alternatively, the following text can be saved as a .REG file and imported to set the kill bit for these controls:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{02BF25D5-8C17-4B23-BC80-D3488ABDDC6B}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{4063BE15-3B08-470D-A0D5-B37161CFFD69}]
"Compatibility Flags"=dword:00000400

Disable file association for QuickTime files

Disable the file association for QuickTime file types to help prevent windows applications from using Apple QuickTime to open QuickTime files. This can be accomplished by deleting the following registry keys:

HKEY_CLASSES_ROOT\QuickTime.*
This will remove the association for approximately 32 file types that are configured to open with the QuickTime Player software.

Disable JavaScript

For instructions on how to disable JavaScript, please refer to the Securing Your Web Browser document. This can help prevent some attack techniques that use the QuickTime plug-in or ActiveX control.

Do not access QuickTime files from untrusted sources

Attackers may host malicious QuickTime files on web sites. To convince users to visit their sites, those attackers often use a variety of techniques to create misleading links, including URL encoding, IP address variations, long URLs, and intentional misspellings. Do not click on unsolicited links received in email, instant messages, web forums, or internet relay chat (IRC) channels. Type URLs directly into the browser to avoid these misleading links. While these are generally good security practices, following these behaviors will not prevent exploitation of this vulnerability in all cases, particularly if a trusted site has been compromised or allows cross-site scripting.