MS02-023: Patch Available for Script in Cookies Reading Cookies Vulnerability (322926)



The information in this article applies to:

  • Microsoft Internet Explorer 5.5 for Windows NT 4.0 SP 1
  • Microsoft Internet Explorer 5.5 for Windows NT 4.0 SP 2
  • Microsoft Internet Explorer 5.5 for Windows Millennium Edition SP 1
  • Microsoft Internet Explorer 5.5 for Windows Millennium Edition SP 2
  • Microsoft Internet Explorer 5.5 for Windows 98 Second Edition SP 1
  • Microsoft Internet Explorer 5.5 for Windows 98 Second Edition SP 2
  • Microsoft Internet Explorer 5.5 for Windows 98 SP 1
  • Microsoft Internet Explorer 5.5 for Windows 98 SP 2
  • Microsoft Internet Explorer 5.5 for Windows 95 SP 1
  • Microsoft Internet Explorer 5.5 for Windows 95 SP 2
  • Microsoft Internet Explorer 5.5 for Windows 2000 SP 1
  • Microsoft Internet Explorer 5.5 for Windows 2000 SP 2
  • Microsoft Internet Explorer version 6 for Windows 2000
  • Microsoft Internet Explorer version 6 for Windows 98
  • Microsoft Internet Explorer version 6 for Windows 98 Second Edition
  • Microsoft Internet Explorer version 6 for Windows NT 4.0
  • Microsoft Internet Explorer version 6 for Windows XP
  • Microsoft Internet Explorer version 6 for Windows Millennium Edition

This article was previously published under Q322926

SYMPTOMS

An information-disclosure vulnerability that affects cookies exists in Internet Explorer. Through scripting that is contained in cookies, a malicious Web site can potentially read or change the contents of a user's cookies. These cookies might contain personal information.

To exploit this vulnerability, the attacker is likely to have to create a Web page that creates a specially formed cookie that contains the script. The attacker then must post the page on a Web site.

The vulnerability does not permit the script to access any other information on the local computer. The vulnerability also does not permit scripting to take any other actions on the computer, such as adding, changing, or deleting data. An attacker must know the exact name of the cookie to access. By itself, this vulnerability provides no means for an attacker to acquire that information.

CAUSE

This vulnerability occurs because of a flaw in how Internet Explorer determines the correct security zone for handling scripts that are embedded in cookies, and how that determination interacts with the zone classification for all cookies. Because cookies are considered to be part of the same domain under the Internet Explorer cross-domain security model, Internet Explorer treats attempts by scripts in cookies to access other cookies to be a valid operation. However, because cookies are not isolated content, but are tied to originating sites, this can provide a means for a Web site to illegally access and work with information that is contained in another site's cookie.

RESOLUTION

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:

328548 How to Obtain the Latest Internet Explorer 6 Service Pack

The update for this problem is included in the "May 15, 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:

321232 MS02-023: May 15, 2002, Cumulative Patch for Internet Explorer

Internet Explorer 5.5 Service Pack 2

The update for this problem is included in the "May 15, 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:

321232 MS02-023: May 15, 2002, Cumulative Patch for Internet Explorer

Internet Explorer 5.5 Service Pack 1

The update for this problem is included in the "May 15, 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:

321232 MS02-023: May 15, 2002, Cumulative Patch for Internet Explorer

STATUS

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.

MORE INFORMATION

For more information about this vulnerability, visit the following Microsoft Web site:

Modification Type:MinorLast Reviewed:11/17/2005
Keywords:kbbug kbfix kbIE550PreSP3fix kbIE600preSP1fix KbSECBulletin KbSECHack kbSecurity KbSECVulnerability kbIE600sp1fix KB322926