Microsoft has issued a temporary fix for a high-profile Internet Explorer 8 vulnerability. This is the bug linked to recent targeted attacks against web pages accessed by nuclear weapons research teams at the US Department of Labor website.
The Fix It, released late on Wednesday, is designed to offer a temporary block against attacks based on the zero-day vulnerability ahead of a more comprehensive patch.
Applying the Fix will not require a reboot, a important factor in corporate environments. Microsoft is withholding details on what the Fix It actually does - at least until after its security gnomes forge a proper patch.
Redmond recommends that all customers using Internet Explorer 8 apply the stop-gap Fix It. Users of other versions of Internet Explorer are not affected and therefore need not worry.
"We have updated Security Advisory 2847140 with an easy one-click Fix It to help protect Internet Explorer 8 customers," said Dustin Childs, group manager of response communications at Microsoft Trustworthy Computing in a statement.
"Customers should apply the Fix It or follow the workarounds listed in the advisory to help protect against the known attacks while we continue working on a security update. Internet Explorer 6, 7, 9 and 10 are not affected."
The Fix It is an easy-to-apply alternative to various workarounds detailed by Microsoft when it admitted there was a serious hole in its browser software late last week. Part of these defences rely on using Microsoft’s free Enhanced Mitigation Experience Toolkit (EMET), which offers added protection against 0-days targeted at browsers on Windows systems that specifically tackle memory corruption-related security bugs.
IE 8 comes pre-installed on Windows 7 systems but users have the straightforward option of upgrading to IE 9 in order to stay out of harm's way, an option unavailable to laggards running Windows XP boxes.
A blog post by Wolfgang Kandek, CTO at cloud security firm Qualys, commenting on the vulnerability and suggested defence tactics can be found here.
Stats from Qualys's BrowserCheck service suggest that 42 per cent of all systems are running IE 8. If successfully exploited, the 0-day vulnerability (CVE-2013-1347) in IE 8 yields full control of compromised Windows machines, allowing hackers to install malware such as the Poison Ivy Trojan.
The exploit has reared its ugly head on several other websites since its initial discovery on a US Department of Labor website on 1 May. Since then the exploit has also been bundled into Metasploit, the popular open-source penetration testing toolkit. ®