IE and Firefox Vulnerability: Remote Code Execution Threat Overview

" The vulnerability, which was widely reported on security blogs, allows an attacker to remotely execute malicious code on a machine that is running IE but also has the Mozilla browser installed." I found this hack to be interesting because how the hack uses both IE and Firefox. Who's at fault? Is it IE for allowing the hack to open a Firefox browser or is it a Firefox flaw, in that it allows execution of the code?

A serious vulnerability that causes Internet Explorer to launch Firefox and execute a malicious payload is sparking debate about exactly who is responsible for the flaw.

The vulnerability, which was widely reported on security blogs, allows an attacker to remotely execute malicious code on a machine that is running IE but also has the Mozilla browser installed. By luring an IE user to a malevolently crafted site, the attacker can cause Firefox to execute the code without first vetting it for security.

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