Third party patches

A time lag between the detection of new vulnerabilites in MS Internet Explorer and the moment when Microsoft releases patches is inevitable.

However, one result has been the appearance and then increasing popularity of third-party fixes. There are already several kinds of these, including homegrown or professional, free and shareware. Sometimes they are actually being sold for good money!

One interesting case took place in December 2003, as described in this story. In short, a vulnerability (or unwanted feature, if you please) in IE allowed somebody to create a special URL which, instead of displaying the actual location of a possibly malevolent webpage, showed a trusted site such as “www.ebay.com”, “www.google.com” or why not, “www.kaspersky.com”.

Tricked by the URL, an user entered confidential information such as PayPal account or e-banking details, believing that the displayed page is actually what Internet Explorer claimed it was. Somebody quickly crafted a rapid fix before Microsoft released a patch and started to freely distribute it on the Internet.

What was not known in the beginning was that the fix itself contained a spyware feature. Moreover, it even had a worse vulnerability which allowed direct execution of code through some specially crafted URLs. So much for a solution which was worse than the problem it tried to fix!

Almost one year later, the story repeats itself. With the Internet Explorer IFRAME buffer overflow having no official solution from Microsoft even two weeks after it was announced and started being actively exploited in viruses, somebody has developed yet another custom IE patch.

Even if this patch may be actually useful in blocking the above mentioned vulnerability, there are some reasons for which we do not recommend such solutions:

1. as it happened with “OpenWares.org” fix, the patch itself may contain programming errors hence opening additional malware entrances in the system
2. the patch may be incompatible with a future Microsoft genuine patch, resulting in unpredictable behaviour
3. the custom patch may fix a bug while at the same time breaking a fully perfectly innocent feature of IE widely used in your organization

And the above list can go on. In short, as somebody else was once saying, “when hitting yourself on the head with a hammer starts to give you headaches, the solution is not to put padding on the hammer.”

Some alternate browsers to tide you over until IE is patched:

Opera
FireFox