Feeds

MS releases grand daughter of all IE security patches

Critical patching time, again

  • alert
  • submit to reddit

Build a business case: developing custom apps

Microsoft released another cumulative patch for Internet Explorer yesterday, which promises to plug up six recently discovered security defects involving the browser.

The patch, for IE 5.01, 5.5 and 6.0, includes the functionality of previously released fixes, as well as tackling the new problems - the most serious of which could allow an attacker to run code of his choice on a victim's machine. Microsoft describes the patch as 'critical', so let's hope it works properly.

Six of the worst

The most serious bug involves a cross-site scripting vulnerability. IE ships with several files that contain HTML on the local file system, one of which contains a flaw that could allow a script to execute as if it were run by the user. This bug could be exploited by an attacker who tricks victims into either visiting a maliciously constructed Web page or opening HTML email containing a poisoned script.

Next up us is an information disclosure vulnerability related to a buggy HTML object, which is designed to provide support for Cascading Style Sheets. Because of the bug, an attacker might be able to read, but not delete or change, data on a local system, MS says.

Moving on, there's an information disclosure vulnerability involving to the handling of script within cookies, which could potentially allow one site to read the cookies of another.

Then there's a zone spoofing vulnerability that could allow a Web page to be incorrectly reckoned to be in the Intranet zone or, in some very rare cases, in the Trusted Sites zone.

Finally there are two variants of a 'content disposition' vulnerability, which relate to how IE handles downloads when a downloadable file's Content-Disposition and Content-Type headers are intentionally malformed. Virus writers might use the technique to disguise the fact that an attachment contains executable content, hence the need for the patch.

As well as plugging up the six vulnerabilities listed above, Microsoft's patch also disables frames in the Restricted Sites zone. The change means that recently released MS email clients (and those with Outlook Email Security Update installed) will disable frames in HTML email by default, blocking the possibility of an HTML email automatically opening a new window or launching the download of an executable. At least that's the idea.

You could read about the problems in more details, and get links to the relevant patch, in Microsoft's advisory on the subject. ®

Related Stories

MS issues monster IE security fix
MS releases mother of all IE security patches
Ditch IE - veteran bug hunter

The essential guide to IT transformation

More from The Register

next story
Rupert Murdoch says Google is worse than the NSA
Mr Burns vs. The Chocolate Factory, round three!
e-Borders fiasco: Brits stung for £224m after US IT giant sues UK govt
Defeat to Raytheon branded 'catastrophic result'
Germany 'accidentally' snooped on John Kerry and Hillary Clinton
Dragnet surveillance picks up EVERYTHING, USA, m'kay?
Snowden on NSA's MonsterMind TERROR: It may trigger cyberwar
Plus: Syria's internet going down? That was a US cock-up
Who needs hackers? 'Password1' opens a third of all biz doors
GPU-powered pen test yields more bad news about defences and passwords
Think crypto hides you from spooks on Facebook? THINK AGAIN
Traffic fingerprints reveal all, say boffins
Microsoft cries UNINSTALL in the wake of Blue Screens of Death™
Cache crash causes contained choloric calamity
prev story

Whitepapers

Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Solving today's distributed Big Data backup challenges
Enable IT efficiency and allow a firm to access and reuse corporate information for competitive advantage, ultimately changing business outcomes.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.