Microsoft issues patch for hole in IE

Microsoft Corp. now has a patch available for the security hole in Internet Explorer Versions 5.5 and 6 that can expose cookie data to malicious hackers.

Online Solutions Ltd., a Finnish security firm that alerted Microsoft to the vulnerability Nov. 1 and released the existence and details of the exploit, before Microsoft issued a patch, first publicized the vulnerability last week.

Microsoft then posted an advisory and recommended that users disable Active Scripts in IE to prevent their cookie data from being stolen. However, disabling active scripts also renders some Web sites unusable.

The vulnerability lies in the ability of a malicious hacker to write an intentionally malformed URL in a Web page address. The action allows a hacker to see the cookies deposited by other Web sites on the users’ hard drive. While proper security practice wouldn’t allow sensitive information to be stored in those cookies, some Web sites do place credit card and other personal information in the cookies.

A malformed Web address link in HTML e-mail would also expose cookie data.

The patch shuts the ability of one Web site to grab information left by another Web site. The patch also addresses three previously undisclosed problems, according to the revised bulletin.

“The first two involve how IE handles cookies across domains,” the bulletin states.

“Although the underlying flaws are completely unrelated, the scope is exactly the same – in each case, a malicious user could potentially craft a URL that would allow them to gain unauthorized access to a user’s cookies and potentially modify the values contained in them.”

The bulletin goes on to say that “the third vulnerability is a new variant of a vulnerability discussed in Microsoft Security Bulletin MS01-051 affecting how IE handles URLs that include dotless IP addresses. … [IE] would treat the site as an intranet site, and open pages on the site in the Intranet Zone rather than the correct zone. This would allow the site to run with fewer security restrictions than appropriate. This vulnerability does not affect IE 6.”

Would you recommend this article?

Share

Thanks for taking the time to let us know what you think of this article!
We'd love to hear your opinion about this or any other story you read in our publication.


Jim Love, Chief Content Officer, IT World Canada

Featured Download

Featured Articles

Cybersecurity in 2024: Priorities and challenges for Canadian organizations 

By Derek Manky As predictions for 2024 point to the continued expansion...

Survey shows generative AI is a top priority for Canadian corporate leaders.

Leaders are devoting significant budget to generative AI for 2024 Canadian corporate...

Related Tech News

Tech Jobs

Our experienced team of journalists and bloggers bring you engaging in-depth interviews, videos and content targeted to IT professionals and line-of-business executives.

Tech Companies Hiring Right Now