July 23rd, 2003, 10:03 PM
Heads up- Unchecked Buffer in DirectX Could Enable System Compromise (819696)
Microsoft Security Bulletin MS03-030
Unchecked Buffer in DirectX Could Enable System Compromise (819696)
Originally posted: July 23, 2003
Who should read this bulletin: Customers using Microsoft® Windows®
Impact of vulnerability: Allow an attacker to execute code on a user’s system
Maximum Severity Rating: Critical
Recommendation: Customers should apply the security patch immediately
* Microsoft DirectX® 5.2 on Windows 98
* Microsoft DirectX 6.1 on Windows 98 SE
* Microsoft DirectX 7.0a on Windows Millennium Edition
* Microsoft DirectX 7.0 on Windows 2000
* Microsoft DirectX 8.1 on Windows XP
* Microsoft DirectX 8.1 on Windows Server 2003
* Microsoft DirectX 9.0a when installed on Windows Millennium Edition
* Microsoft DirectX 9.0a when installed on Windows 2000
* Microsoft DirectX 9.0a when installed on Windows XP
* Microsoft DirectX 9.0a when installed on Windows Server 2003
* Microsoft Windows NT 4.0 with either Windows Media Player 6.4 or Internet Explorer 6 Service Pack 1 installed.
* Microsoft Windows NT 4.0, Terminal Server Edition with either Windows Media Player 6.4 or Internet Explorer 6 Service Pack 1 installed.
DirectX consists of a set of low-level Application Programming Interfaces (APIs) that are used by Windows programs for multimedia support. Within DirectX, the DirectShow technology performs client-side audio and video sourcing, manipulation, and rendering.
There are two buffer overruns with identical effects in the function used by DirectShow to check parameters in a Musical Instrument Digital Interface (MIDI) file. A security vulnerability results because it could be possible for a malicious user to attempt to exploit these flaws and execute code in the security context of the logged-on user.
An attacker could seek to exploit this vulnerability by creating a specially crafted MIDI file designed to exploit this vulnerability and then host it on a Web site or on a network share, or send it by using an HTML-based e-mail. In the case where the file was hosted on a Web site or network share, the user would need to open the specially crafted file. If the file was embedded in a page the vulnerability could be exploited when a user visited the Web page. In the HTML-based e-mail case, the vulnerability could be exploited when a user opened or previewed the HTML-based e-mail. A successful attack could cause DirectShow, or an application making use of DirectShow, to fail. A successful attack could also cause an attacker’s code to run on the user’s computer in the security context of the user.
* By default, Internet Explorer on Windows Server 2003 runs in Enhanced Security Configuration. This default configuration of Internet Explorer blocks the e-mail-based vector of this attack because Microsoft Outlook Express running on Windows Server 2003 by default reads e-mail in plain text. If Internet Explorer Enhanced Security Configuration were disabled, the protections put in place that prevent this vulnerability from being exploited would be removed.
* In the Web-based attack scenario, the attacker would have to host a Web site that contained a Web page used to exploit these vulnerabilities. An attacker would have no way to force users to visit a malicious Web site outside the HTML-based e-mail vector. Instead, the attacker would need to lure them there, typically by getting them to click a link that would take them to the attacker's site.
* The combination of the above means that on Windows Server 2003 an administrator browsing only to trusted sites should be safe from this vulnerability.
* Code executed on the system would only run under the privileges of the logged-on user.
Microsoft DirectX 9.0a Critical
Microsoft DirectX 9.0a when installed on Windows Server 2003 Important
Microsoft DirectX 8.1 Critical
Microsoft DirectX 8.1 on Windows Server 2003 Important
Microsoft DirectX 7.0a on Windows Millennium Edition Critical
Microsoft DirectX 7.0 on Windows 2000 Critical
Microsoft Windows Media Player 6.4 or Internet Explorer 6 Service Pack 1 when installed on Windows NT 4.0 Critical
Microsoft Windows Media Player 6.4 or Internet Explorer 6 Service Pack 1 when installed on Windows NT 4.0, Terminal Server Edition Critical
The above assessment is based on the types of systems affected by the vulnerability, their typical deployment patterns, and the effect that exploiting the vulnerability would have on them.
Vulnerability identifier: CAN-2003-0346
Microsoft tested Microsoft DirectX 9.0a, Microsoft DirectX 8.1, Microsoft DirectX 7.0, Microsoft DirectX 7.0a on Windows Millennium Edition, DirectX 6.1 on Windows 98 SE, DirectX 5.2 on Windows 98, Microsoft Windows NT 4.0 with Windows Media Player 6.4 and Internet Explorer 6 Service Pack 1 installed, Microsoft Windows NT 4.0, Terminal Server Edition with Windows Media Player 6.4 and Internet Explorer 6 Service Pack 1 installed to assess whether they are affected by this vulnerability. Previous versions are no longer supported and may or may not be affected by this vulnerability
Frequently asked questions
What’s the scope of this vulnerability?
This is a buffer overrun vulnerability. An attacker who successfully exploited the vulnerability could, in the worst case, run code of his or her choice on a user’s system. The attacker's code would run with the same privileges as the user: any restrictions on the user's ability to change the system would apply to the attacker's code. For example, if the user were prevented from deleting files on the hard disk, the attacker's code would similarly be prevented. Conversely, if a user were using an account with high privileges, such as an administrator's account, the attacker's code would also run with the same high privileges. The vulnerability exists in the component responsible for parsing MIDI files. This function is included in a component of DirectX known as DirectShow.
N00b> STFU i r teh 1337 (english: You must be mistaken, good sir or madam. I believe myself to be quite a good player. On an unrelated matter, I also apparently enjoy math.)
July 24th, 2003, 01:01 AM
Why they just CAN'T make it right? Talking about Micro$oft [the answer is inside]