Software giant forced to act following discovery of new vulnerability in several versions of web browser.
Software giant Microsoft has moved to close down an Internet Explorer security hole that has already been used by hackers to carry out targeted attacks.
The vulnerability is reported to be present in Internet Explorer versions 6, 7 and 8.
In a security advisory post on the Microsoft Technet site, the firm described the issue as a “remote code execution” vulnerability that affects the way Internet Explorer accesses deleted and improperly allocated items.
“The vulnerability may corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user within Internet Explorer,” stated the post.
“An attacker could host a specially crafted website that is designed to exploit this vulnerability through Internet Explorer and then convince a user to view the website.”
Hackers could also use the vulnerability to take over a user’s machine, Microsoft warned, allowing them to create new accounts or delete data.
“An attacker who successfully exploited this vulnerability could gain the same users rights as the current user,” the advisory explained.
Microsoft has issued some “workaround” advice for users concerned by the problem, and said it may require an out-of-cycle patch to solve completely.
In the meantime, the firm is advising users to apply the Microsoft Fix It, MSHTML Shim Workaround, and to deploy an Enhanced Mitigation Experience Toolkit (EMET), as both of these should make it harder for hackers to exploit the vulnerability.
The company is also instructing users to set their browser security settings to high, which should block ActiveX Controls and Active Scripting.
For more information, visit the Microsoft Technet site.