Random insights of our daily work
Recently, while attending a conference, I observed an unusual occurrence in my terminal emulator: terminal tab windows were getting highlighted without any apparent notification within the shell session. Time to unpack our trusty debugging tools to uncover the mystery of these activities.
Linux offers a lot of tools to understand internals, today we'll analyze the network stack with zero tools installed.
Negative permissions have always been bad practice, with the help of container tooling they can be bypassed too.
We've been part of a team that audited c-ares. This is a writeup of how we discovered that DNS query identifiers generated by c-ares are not always properly random which lead to CVE-2023-31147.
Today, we would like to present a lesser-known feature of the Linux kernel. Instead of launching a program from a file system, regardless of whether it's virtual or not, it is also possible to embed a user-space program directly into the kernel image itself and start it from there.
The Embedded Open Source Summit in Prague offered valuable insights and connections for our company, focusing on Linux and security, as our first major conference since the pandemic.
Stack canaries are a common security feature to mitigate buffer-overflows. However, it's value is generated differently in every libc-implementation, which has security implications.
Our last blog post on Linux mount namespaces explored ways to restrict access to the file system. In this post we'll show how to restrict access to the network.
Lately we've been facing strange build errors on one of our build servers. The root cause was quite surprising.
Linux offers a variety of mechanisms to confine a process, one of them are namespaces. Today they are mostly used as foundation for Linux containers. In this blog post we'll demonstrate how namespaces can be used to restrict access to the file system for a given process and all its children.
Understanding certain kernel internals is not only useful for persons that intend developing kernel related software.
An overview about x86 firmware security and Heads, a project aiming to gain more trust in the boot process.
ALPSS 2022 took place again and here's what happened
This blog post gives an overview of EROFS vs. SquashFS and tries to compare them with a simple benchmark.
In 2021 we switched to ProtonMail and figured the hard way that it is not the right thing for us.
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