By default, when starting a new session using IE8's InPrivate Browsing feature, toolbars and Browser Helper Objects are disabled. This is done to help protect the user's privacy: many toolbars and extensions maintain their own navigation/search/etc history...

Someone recently asked me for a list of custom HTTP request and response headers introduced by the IE team over the years. Here's the list I've come up with so far (including a few that were introduced before I joined the team): Request Headers ...

Not exactly IE related, although IE8 is included in Windows 7: Until July 11th, Windows 7 upgrade pre-orders are available for half-price . Home Premium is $50, and Professional is $100. -Eric

My thoughts about Mozilla's Content Security Policy proposal were just published over on the IEBlog. I actually have quite a bit more to say (at even greater length :-) about declarative security mechanisms, and some more technical feedback specific to...

It isn't directly related to Internet Explorer, but Mark Russinovich's Inside Windows7 User Account Control article over on TechNet provides an illuminating explanation of why UAC isn't a security boundary, but why it helps protect against malware anyway...

Update: IE9 includes improved handling of Mixed Content. Click to learn more... Background As we developed Internet Explorer 8, we spent quite a bit of time pondering what to do about IE7’s infamous “Mixed Content” warning prompt...

Applications which host the WebOC (Web Browser control) may choose to support popups and new windows by hooking the NewWindow3 event and returning in ppDisp a pointer to a new, hidden, non-navigated WebBrowser object or InternetExplorer object. If such...

Windows 7's updated crypto stack (schannel.dll, etc) offers support for TLSv1.1 and TLSv1.2. While disabled by default in IE8 (for compatibility reasons; some legacy sites will fail to connect when the updated TLS version is offered) the new protocol...

Q: My ASP.NET site's menus show as blank/white when my page is rendered in IE8 standards mode. The menus only work if I turn on compatibility view. What's up with that? A: This is actually a standards-compliance bug in the ASP.NET framework. A fix...

Windows Vista SP1 introduced an interesting new memory protection known as SEHOP, which works with other memory protection techniques (like DEP/NX , ASLR, etc) to help prevent exploitation of a specific type of memory-related vulnerability known as SEH...

Version 4 of the Safari web browser now supports the HTTPOnly directive for cookies introduced by IE6 SP1. Now, all major browsers support the directive, which can help mitigate the impact of XSS exploits. Safari 4 also now supports the X-FRAME-OPTIONS...

About the Vary Response Header As described in the HTTP/1.1 specification ( RFC2616 ), the Vary response header allows a cache to determine if a cached (still fresh) response may be returned for a subsequent request, based on whether or not the new...

Internet Explorer (actually, WinINET, the network stack beneath IE) prohibits use of certain ports for HTTP(S) connections. The intent of this blocking is to prevent Cross Service/Protocol Request Forgery attacks. For instance, an attacker could use a...

Background One of the interesting attacks which makes the rounds every few years concerns the ability of web pages to use CSS to detect whether or not certain URLs have been visited. Given a sufficiently large set of URLs to probe, a website may be able...

Over on the BlueHat blog, security researcher Manuel Caballero wrote up an interesting post on how Silverlight avoids exposing unsecured private browser APIs to abuse from RIA content. Anyone building ActiveX controls that take untrusted input should...

Another question from the audience today: Q: I like IE8's InPrivate Browsing feature , but I'm worried that it won't let me see what my kids are up to. Can I prevent them from using it? A: Yes. When you enable the Windows Parental Controls feature...

The latest IE cumulative update shipped today ; download it from WindowsUpdate when you get a chance. Over on the Security Research and Defense blog , there's an in-depth discussion of the security bug discovered in IE8 at the Pwn2Own contest at CanSecWest...

We've had a few folks write to the IEBlog asking " How can I disable the little blue accelerator icon that appears when text is selected in a HTML page? " For end users, the answer is straightforward: Click Tools > Internet Options > Advanced...