For the second time in a week, hackers have discovered a previously unknown bug in Microsoft’s Internet Explorer (IE) browser that could be exploited to run unauthorized software on a Windows computer. This latest bug, reported Thursday, could be exploited to seize control of a Windows system and has been given a “high risk” rating by the FrSIRT security website.Although “proof-of-concept” code showing how this vulnerability could be exploited has been published, making the bug a more serious concern, there are some mitigating factors. Attackers would first need to trick users into visiting a specially coded webpage and then somehow get them to perform certain actions, such as writing “specific text in a text field,” before they could run their malicious software, FrSIRT said. The risk is further mitigated by the fact that the bug reportedly does not affect the latest versions of Microsoft’s Windows and Windows Server 2003 operating systems, FrSIRT said. Because of these mitigating factors, Microsoft has decided not to fix the bug in a security update to Internet Explorer. “The vulnerability cannot be used to execute code on a user’s system without multiple user actions that are uncommon in typical Web browsing scenarios,” Microsoft said in a statement provided by its public relations agency. “Due to the significant mitigating factors … we have determined that the issue would be most appropriately addressed in a service pack delivery rather than a security update.” Microsoft is not aware of any attacks made so far that were intended to exploit the vulnerability, the statement said.Users who do not want to wait for the next IE service pack can avoid problems by changing IE’s security settings so that the browser no longer prompts users before delivering active content, said Matthew Murphy, the researcher who discovered the bug. “The vulnerability at issue depends fundamentally on a weakness in the browser’s method of prompting when warning users of potentially unsafe active content on a Web page,” he said in a full-disclosure mailing list posting.This workaround may prevent IE from working properly on websites that depend on ActiveX controls, however, he warned.Internet Explorer continues to be a prime target for attackers, with Microsoft having to patch a handful of publicly disclosed bugs in its latest security update for the product, which was released April 11.Last Sunday, researcher Michael Zalewski posted details of a similarly critical bug in IE to Full Disclosure. Security firm Secunia rates Zalewski’s bug as “highly critical.”Microsoft was not immediately available for comment on this latest vulnerability. — Robert McMillan, IDG News ServiceThis article is posted on our Microsoft Informer page. For more news on the Redmond, Wash.-based powerhouse, keep checking in.For related coverage, read Firefox Supporters Set Sights on Internet Explorer With Campaign and Microsoft Debuts New Internet Explorer Beta.Check out our CIO News Alerts and Tech Informer pages for more updated news coverage. Related content feature 13 essential skills for accelerating digital transformation IT leaders too often find themselves behind on business-critical transformation efforts due to gaps in the technical, leadership, and business skills necessary to execute and drive change. By Stephanie Overby Jun 05, 2023 12 mins Digital Transformation IT Skills tip 3 things CIOs must do now to accurately hit net-zero targets More than a third of the world’s largest companies are making their net-zero targets public, yet nearly all will fail to hit them if they don’t double the pace of emissions reduction by 2030. This puts leading executives, CIOs in particul By Diana Bersohn and Mauricio Bermudez-Neubauer Jun 05, 2023 5 mins CIO Accenture Emerging Technology case study Merck Life Sciences banks on RPA to streamline regulatory compliance Automated bots assisted in compliance, thereby enabling the company to increase revenue and save precious human hours, freeing up staff for higher-level tasks. By Yashvendra Singh Jun 05, 2023 5 mins Digital Transformation Robotic Process Automation feature Expedia poised to take flight with generative AI CTO Rathi Murthy sees the online travel service’s vast troves of data and AI expertise fueling a two-pronged transformation strategy aimed at growing the company by bringing more of the travel industry online. By Paula Rooney Jun 02, 2023 7 mins Travel and Hospitality Industry Digital Transformation Artificial Intelligence Podcasts Videos Resources Events SUBSCRIBE TO OUR NEWSLETTER From our editors straight to your inbox Get started by entering your email address below. Please enter a valid email address Subscribe