.NET Security Blog

One enhancement to the v2.0 SN tool that may not get noticed right away is that it now has the ability to work with PKCS #12 PFX files in addition to SNK files. The logic here is that a self signed certificate stored in a PFX file is the moral equivalent...

We've previously discussed where the security policy files are located on your disk . Depending on how you install the CLR, you may find that the actual security .config files are missing -- what does the CLR do if it can't find them? Even if there...

When installing the v2.0 .NET redist package, you'll find that the .Net Configuration MMC snap-in is missing . As of v2.0, we've moved this tool to the SDK package, which you can download here: [x86] [ x64 ] [ IA64 ]. The split of security tools between...

Deny and PermitOnly cannot be used to create an effective sandbox because like Assert , they function as stack walk modifiers -- meaning they modify the current call stack and not the grant set of an assembly. We talked about this previously in Assert...

The new UAC blog (formerly LUA, formerly UAP) has up a good post on the six security policy settings that have been introduced to control how UAC works. As the Vista betas start coming out and people can start to play with UAC, knowing that some of these...

In my last post , I mentioned that application scoped isolated storage only works if you're running in a ClickOnce application. That begs the question -- how do I tell if I'm currently running in the context of a ClickOnce application? You can see...

Isolated storage introduced a new scope in v2.0 of the CLR to work with ClickOnce applications. Application scoped Isolated storage is backed by the application's data directory. This enables scenarios where your isolated storage data will flow forward...

As part of planning for our next release, we're interested in collecting some data on how you customize your security policy. We're intereseted in as much information as you have to offer. For instance, do you mainly add code groups to the machine level...

We previously saw that the SkipVerification demand for calling a method with unverifiable code occurs at JIT time rather than at runtime. Two other types of demands also occur at JIT time, LinkDemands and InheritenceDemands. An InheritenceDemand will...

Nicole Calinoiu , one of our developer security MVPs, has just posted a good description of the problems that occur when using PrincipalPermission with impersonation and finalizers . The key thing to take away from this is that impersonation occurs on...

Over the weekend, Mike Rousos (a BCL tester who's been temporarily drafted onto the security team) posted an interesting piece about the new BCL registry security support on the BCL blog . While the title mentions RegistryPermission, the post is actually...

On one of our internal mailing lists, someone was recently surprised that calling RSACryptoServiceProvider::Encrypt on the same bytes with the same instance of the RSA object resulted in two completely different output bytes arrays. The reason is that...

A few people have noticed that the ADMHost sample is not set up to do mixed mode debugging by default. If you're working with this sample and you'd like to debug through both halves of the host, you'll need to enable this mode. Right click on the...

It's that time of year again when most of the offices around Microsoft start going dark, and I'll be adding 42/2221 to that list for the next couple of weeks as I head off to New York for Christmas. My traditional weather.com check shows that I should...

Now that Whidbey's out the door, it's time to look at what we want to do in future releases. If you've run into any issues with the crypto classes or with ClickOnce let me know! You can leave comments here or file requests in the MSDN Product Feedback...

To add to our other lists of "What's New in Whidbey Security", Rudolph Araujo and Shanit Gupta have a nice roundup of new security features posted on the Microsoft .NET Framework Developer Center. They've got them categorized, summarized, and provide...

The Process class has a LinkDemand and an InheritenceDemand for FullTrust on it. This means that if your assembly is not fully trusted, it will be unable to kick off new Processes or get information about running processes. One implication is that assemblies...

The general concepts of Authenticode signing an assembly are well understood -- they mostly correlate directly to the standard Win32 concept of a signed catalog. However, there are a few places where managed code plays differently, and sometimes these...

Jeffery Brown has posted his paper on the Xbox 360 CPU Design from the Fall Processor Forum over on IBM's DeveloperWorks. Since I have my degree in hardware design , I always find these types of things interesting. While this paper is at a relatively...

The RSACryptoServiceProvider class provides two methods, Encrypt and Decrypt which seem to be the managed counterparts to CAPI's CryptEncrypt and CryptDecrypt functions. However, if you try to encrypt using CAPI and decrypt using managed code, you'll...

If you're developing a partial trust ClickOnce application and are looking for its process in Task Manager or Process Explorer, you might be surprised that you can't find it listed anywhere. What you will see however is a process named AppLaunch.exe....

When starting to play with CAS a lot of people come up with toy programs that simply do a Demand for some permission or another, then copy that program to various locations that will cause it to be granted different permission sets. It's generally a surprise...

Sometimes, especially when working on large projects (such as, I don't know, say ... the CLR), you find yourself debugging a problem where you don't know where a component is built from. Depending on the problem, it might be useful to get to the sources...

The RSA class exposes an ExportParameters method which allows you to get at the raw RSA key in the form of an RSAParameters structure. What that structure contains isn't very obvious to people not familiar with how RSA works. With fields named P, Q, D...

One common mistake that people make when using managed encryption classes is that they attempt to store the result of an encryption operation in a string by using one of the Encoding classes. That seems to make sense right? After all, Encoding.ToString...