Kernel

Linux and ASLR: kernel/randomize_va_space

ASLR protects the Linux kernel and programs against different attacks. It can be tuned with the randomize_va_space setting to provide different protections.

Summary of Linux and ASLR: kernel/randomize_va_space

Configuring ASLR with randomize_va_space The Linux kernel has a defense mechanism named address space layout randomization (ASLR). This setting is tunable with the randomize_va_space setting. Before making changes to this setting, it is good to understand what this Linux security measure actually does and how it works. Understanding ASLR In 2001 the term ASLR was first introduced as a patch to the Linux kernel. Its main goal was to randomize memory segments to make abuse by malicious programs harder.

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Linux hardening with sysctl settings

The Linux kernel can be secured as well. Learn how system hardening principles can be applied using sysctl settings.

Summary of Linux hardening with sysctl settings

The GNU/Linux kernel powers a lot of systems, from big mainframes to the Android device in your pocket. If you want to achieve more security on your Linux systems, it would make sense to start hardening there, right? While securing the kernel looks easy at first sight, there is more to it than initially meets the eye. We will have a look at some kernel options and how to select the best sysctl values for Linux systems.

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Linux kernel security and how to improve it

Every system is as strong as its weakest link, especially the system kernel. This article explains Linux kernel security, what we can do and how to do so.

Summary of Linux kernel security and how to improve it

Every system is as strong as its weakest link. In the case of an operating system like Linux, one weakness in the kernel could result in a security breach. This article covers the Linux kernel features and how they work. Kernel features Live kernel patching As the kernel is similar to other software, it receives updates to improve it. Now and then a security weakness is discovered in one of the subsystems of the Linux kernel.

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Livepatch: Linux kernel updates without rebooting

Livepatch is a feature to do live kernel patching for Linux systems. It allows applying security updates without rebooting the system. Learn how it works!

Summary of Livepatch: Linux kernel updates without rebooting

If you run a Linux server, software patching is a task that will have to be performed on a regular basis. Although most programs can be auto-restarted with a tool like needrestart, there is one exception: the kernel. Wouldn’t it be a nice if we could update the kernel without the mandatory reboot? Here is livepatch, the feature of the Linux kernel that makes it possible. Let’s discover how it works and if you can use it on your system.

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Monitor file access by Linux processes

Linux is powerful with the help of small utilities like lsof and strace. They help with monitoring disk and file activity, of new and running processes.

Summary of Monitor file access by Linux processes

Processes are the running workforce on a Linux system. Each process has a particular goal, like forking child processes, handling incoming user requests of monitoring other processes. As a system administrator or IT auditor, you might want to know at some point what disk activity occurs in a process. In this article, we have a look at a few options to quickly reveal what is occuring in a process, including disk and file activity.

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