Niels Tanis

Information & Communications Technology

.NET ASP.NET ASP.NET Core Security Application Security DevSecOps .net core C#

Amersfoort, Utrecht, Netherlands

Niels Tanis

Security Researcher

Niels Tanis has got a background in .NET development, pentesting and security consultancy. He also holds the CSSLP certification and has been involved in breaking, defending and building secure applications. He joined Veracode in 2015 and right now he works as a security researcher on a variant of languages and technologies related to Veracode’s Binary Static Analysis service. He is married, father of two and lives in a small village just outside Amersfoort, The Netherlands.

Current sessions

Securing your .NET application software supply-chain

With our complete software development process becoming more complex we also got a lot more security problems to deal with. What starts with code and ends with releasing/deploying software is also being referred at as the software-supply chain. The software supply-chain consists of a lot of moving parts. Each of them facing their own security risks starting from access to source code, compromised third-party libraries and tools, or even hacked build servers. For example with SolarWinds the compromised build server added malicious functionality to the end product used by their customers. And a tool called CodeCov had their upload script compromised which resulted in it stealing all used access-keys.
In this session we'll get hands-on with securing a .NET application it's supply chain and look how we can limit the security risks in all the different area's. We're going to use the guidance of Google's SLSA and using concepts like Software Bill Of Materials (SBOM).


Sandboxing .NET assemblies for fun, profit and of course security!

In our current way of developing .NET applications we rely a lot on third-party libraries developed by others. This of course has a lot of benefits from productivity perspective because there is no need to write needed functionality from scratch.
But by using in a third-party library you also pull in it's issues and possibly security problems that are found over time. What does the library do? And what type of other libraries and/or functionality does it rely on? What do the projects/people behind it do for security?
If we develop a .NET application using external libraries can we improve our security posture? Other new technologies like WebAssembly introduced a concept of nano-process, which allows the developer to limit the capabilities available for an external module by creating a restricted sandbox for it. Could we maybe do the same in .NET? In the old days we could use AppDomains and Code-Access Security (CAS) to achieve that, but with the introduction .NET Core there only is a single AppDomain and CAS has been deprecated.
Luckily with .NET Core we did get more internals exposed on AssemblyLoadContext and in this session we're going to create a sandbox using that. A restricted sandbox that limits the functionality available that will improve the security posture of our application!


The Rise of Software Supply-Chain Attacks – How Secure is your .NET Application?

In the early days, breaking into systems (hacking) mostly consisted of finding machines that where connected to the internet and exposed all their services. In some way the industry became better in locking down infrastructure and access and the attacks focused more on applications finding issues like SQL injection and Cross-Site Scripting. With the latest move to ‘DevOps’ and the use of build pipelines for CI/CD, with Azure DevOps or GitHub Actions, attacks even have become a lot more sophisticated. What if the used container images and/or 3rd party libraries contain vulnerabilities? With cloud native approaches like Azure Functions our application landscapes have become a lot more complex giving hackers more opportunities because of the increased attack surface. All steps we need to take to develop, test and release our software can be referred to as the software supply chain, which has become a lot more complicated.
In this session we'll take a .NET application and go through the different area's of the supply chain, identify the security issues, and possible ways of resolving those issues!