Firefox “firefoxurl” URI Handler Registration Vulnerability
Written by Vygantas Lipskas on July 10, 2007
Secunia reported today about a new exploit for Firefox 2.0.0.4 (might affect previous builds as well).
A vulnerability has been discovered in Firefox, which can be exploited by malicious people to compromise a user’s system.
Solution:
Do not browse untrusted sites.
Disable the “Firefox URL” URI handler.
Thor Larholm noted:
There is an input validation flaw in Internet Explorer that allows you to specify arbitrary arguments to the process responsible for handling URL protocols. This is the same type of input validation vulnerability that I discovered in the Safari 3 beta.
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Disable the “Firefox URL” URI handler.
how ?
So far it seems work in this way:
Open Windows Explorer, like enter My Computer (Not Firefox or any other browser). Click “Tools” in the top menu, find “Folder Options…”
Select “File Types”, find:
(NONE) Firefox URL
Delete it.