Software Engineering Institute

A vulnerability exists in the way Apple QuickTime handles specially crafted Real Time Streaming Protocol (RTSP) URL strings. An attacker may be able to craft a QTL file to take advantage of this vulnerability. However, there are other attack vectors that do not involve QTL files. According to MOAB-01-01-2007:

By supplying a specially crafted string (rtsp:// [random] + semicolon + [299 bytes padding + payload]), an attacker could overflow a stack-based buffer, using either HTML, Javascript or a QTL file as attack vector, leading to an exploitable remote arbitrary code execution condition.
Note that since QuickTime is a component of Apple iTunes, iTunes installations are also affected by this vulnerability. We are aware of publicly available proof-of-concept code that exploits this vulnerability.

A remote, unauthenticated attacker may be able to execute arbitrary code or cause a denial of service.

Apply Update
This issue is addressed in Apple Security Update 2007-001. An update for Mac OS X is available on Apple Downloads and via Software Update. An update for Microsoft Windows XP and 2000 systems is availble via the Apple Software Update application installed with QuickTime 7.1.3.

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 the QuickTime plug-in for Mozilla-based browsers

Users of Mozilla-based browsers, such as Firefox can disable the QuickTime plugin, as specified in the PluginDoc article Uninstalling Plugins.

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. In order 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.