A vulnerability exists in Internet Explorer that could allow an attacker to cause the wrong name to appear in a File Download dialog box. An attacker could exploit this vulnerability in an attempt to fool a user into downloading an unsafe file.

The vulnerability would not provide any way for the attacker to override normal Windows behavior with respect to the download. That is, the vulnerability would not provide a way for the attacker to force the user to accept the download; the user could cancel the operation in the dialog box.

This vulnerability exists because it is possible to manipulate the HTML header information in a Web page to make the Internet Explorer File Download dialog box display the wrong file name and type. By initiating a file download and using this vulnerability to misrepresent the name and type of file being downloaded, an attacker could create a situation in which the user might allow a program file to run.

• Internet Explorer 6
• Internet Explorer 5.5 Service Pack 2
• Internet Explorer 5.5 Service Pack 1
• Internet Explorer 5.01 Service Pack 2 on Windows 2000 only

Internet Explorer 6

To resolve this problem, obtain the latest service pack for Internet Explorer 6. For additional information, click the following article number to view the article in the Microsoft Knowledge Base: The update for this problem is included in the "February 11, 2002, Cumulative Patch for Internet Explorer." For additional information about how to obtain this patch, click the article number below to view the article in the Microsoft Knowledge Base:

Internet Explorer 5.5 Service Pack 2

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that you determine are at risk of attack. Evaluate your computer's physical accessibility, network and Internet connectivity, and other factors to determine the degree of risk to your computer. See the associated Microsoft Security Bulletin (http://www.microsoft.com/technet/security/bulletin/ms02-005.mspx) to help determine the degree of risk. This fix may receive additional testing. If your computer is sufficiently at risk, Microsoft recommends that you apply this fix now. Otherwise, wait for the next Internet Explorer 5.5 service pack that contains this fix.

To resolve this problem immediately, download the fix by following the instructions later in this article or contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The update for this problem is included in the "February 11, 2002, Cumulative Patch for Internet Explorer." For additional information about how to obtain this patch, click the article number below to view the article in the Microsoft Knowledge Base:

Internet Explorer 5.5 Service Pack 1

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that you determine are at risk of attack. Evaluate your computer's physical accessibility, network and Internet connectivity, and other factors to determine the degree of risk to your computer. See the associated Microsoft Security Bulletin (http://www.microsoft.com/technet/security/bulletin/ms02-005.asp) to help determine the degree of risk. This fix may receive additional testing. If your computer is sufficiently at risk, Microsoft recommends that you apply this fix now. Otherwise, wait for the next Internet Explorer 5.5 service pack that contains this fix.

To resolve this problem immediately, download the fix by following the instructions later in this article or contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The update for this problem is included in the "February 11, 2002, Cumulative Patch for Internet Explorer." For additional information about how to obtain this patch, click the article number below to view the article in the Microsoft Knowledge Base:

Internet Explorer 5.01 Service Pack 2 on Windows 2000 Only

The update for this problem is included in the "February 11, 2002, Cumulative Patch for Internet Explorer." For additional information about how to obtain this patch, click the article number below to view the article in the Microsoft Knowledge Base: This update is also available in Internet Explorer 5.01 Service Pack 3 for Windows 2000. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

Internet Explorer 6

Microsoft has confirmed that this problem may cause a degree of security vulnerability in Microsoft Internet Explorer 6. This problem was first corrected in Internet Explorer 6 Service Pack 1.

Internet Explorer 5.5

Microsoft has confirmed that this problem may cause a degree of security vulnerability in Microsoft Internet Explorer 5.5.

Internet Explorer 5.01

Microsoft has confirmed that this problem may cause a degree of security vulnerability in Microsoft Internet Explorer 5.01.To resolve this problem, obtain the latest service pack for Internet Explorer 5.01 for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

For more information about this vulnerability, visit the following Microsoft Web site: For additional information about the "February 11, 2002, Cumulative Patch for Internet Explorer", click the article number below to view the article in the Microsoft Knowledge Base: