Third of Internet Explorer users at risk from active attacks

Microsoft confirms both IE9 and IE10 contain vulnerability, urges customers to upgrade to IE11; leaves Vista users out in the cold

Microsoft claims said both Internet Explorer 10 and its predecessor, IE9, have been under attack by hackers exploiting an unpatched flaw in the browsers.

The extension of the vulnerability to IE9 followed confirmation earlier yesterday that active attacks are compromising the newer IE10 and hijacking PCs running the browser.

"Microsoft is aware of limited, targeted attacks against Internet Explorer 9 and 10. As our investigation continues, we recommend customers upgrade to Internet Explorer 11 for added protection," a Microsoft spokesperson said via email.

With both IE9 and IE10 vulnerable and under attack, it means that about a third of all those using Internet Explorer are at risk.

According to Web analytics vendor Net Applications, IE9 accounted for 15.3% of the total IE user share last month; IE10's share was 15.9%. Together, the two editions represented 31.2% of Internet Explorer's January user share.

Milpitas, Calif.-based FireEye was the first to spot the attacks, and said that they had been aimed at IE10 as part of a campaign targeting current and former U.S. military personnel when they visited the Veterans of Foreign Wars (VFW) website.

While FireEye said it identified the "zero-day" vulnerability -- a term to indicate that the flaw is currently unpatched -- on Feb. 11, yesterday San Diego security company Websense said it had found evidence that the exploit may have been used as early as Jan. 20, or more than three weeks ago.

Websense also speculated that those earlier attacks had been aimed at visitors to a French aerospace association's website. Members of the organization, GIFAS (Groupement des Industries Francaises Aeronautiques et Spatiales), include defense and space contractors and subcontractors.

GIFAS is best known to the general public as the sponsor, through a subsidiary, of the Paris Air Show, an annual extravaganza where aircraft makers, both commercial and military, strut their newest wares.

Microsoft's advice to customers that they upgrade to IE11 was not possible for those still running Windows Vista. That 2007 operating system cannot run either IE10 or IE11. Most Vista users are likely running IE9, since Microsoft automatically upgraded their copies of from IE7 or IE8 to the then-new IE9 in the first half of 2012.

The only silver lining is that few Windows users run Vista: Last month, the oft-disparaged OS represented just 3.6 per cent of all editions of Windows.

Microsoft has not said if it will issue an "out-of-band" security update -- a rush fix shipped before the next regularly-scheduled Patch Tuesday of March 11 -- or yet issued a formal security advisory. It will certainly do the latter, and at that time may, as it often does, provide a work-around to protect IE9 and IE10 users.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His email address is

> >

Read more about security in Computerworld's Security Topic Center.

Join the CSO newsletter!

Error: Please check your email address.

Tags web appsnet applicationssecurityMicrosoftFireEyeMalware and Vulnerabilities

More about AppleFireEyeMicrosoftTopicWebsense

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Gregg Keizer

Latest Videos

  • 150x50

    CSO Webinar: Will your data protection strategy be enough when disaster strikes?

    Speakers: - Paul O’Connor, Engagement leader - Performance Audit Group, Victorian Auditor-General’s Office (VAGO) - Nigel Phair, Managing Director, Centre for Internet Safety - Joshua Stenhouse, Technical Evangelist, Zerto - Anthony Caruana, CSO MC & Moderator

    Play Video

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

More videos

Blog Posts

Market Place