(Almost) undetectable hardware-based rootkits
Fourth-Generation Rootkits
We look at the history of the rootkit, including its newest incarnation, the DR RootKit.
Originally, I intended to write an article about the current state of rootkits and the tools that could be used to detect them. But I ran into a slight problem – the more modern rootkits tend to be really good at avoiding detection. By really good, I mean that you're unlikely to detect them unless you take action, such as a detailed analysis of a system memory dump, for example, comparing the actual kernel image with the expected.
History Lesson
Traditional rootkits were relatively simplistic programs, often running as a standalone daemon providing backdoor access. These were generally easy to detect by looking for a new process or newly installed software, which led attackers to start subverting system binaries. In turn, this led to attackers installing modified system binaries, such as hacked versions of OpenSSH that have a hard-coded administrative username and password to get root-level access. With the advent of tools such as Tripwire and the increasingly common use of package managers that can verify the integrity of installed files, such as RPM and dpkg, these became easy to detect [1].
Kernel-Based Rootkits
Soon attackers realized that more sophisticated hiding and subversion methods were needed to control a system, which led to kernel-based rootkits. By modifying the system call table, an attacker can avoid detection easily because, simply put, they control what you are seeing and how your programs are executing.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
System76 Releases COSMIC Alpha 7
With scores of bug fixes and a really cool workspaces feature, COSMIC is looking to soon migrate from alpha to beta.
-
OpenMandriva Lx 6.0 Available for Installation
The latest release of OpenMandriva has arrived with a new kernel, an updated Plasma desktop, and a server edition.
-
TrueNAS 25.04 Arrives with Thousands of Changes
One of the most popular Linux-based NAS solutions has rolled out the latest edition, based on Ubuntu 25.04.
-
Fedora 42 Available with Two New Spins
The latest release from the Fedora Project includes the usual updates, a new kernel, an official KDE Plasma spin, and a new System76 spin.
-
So Long, ArcoLinux
The ArcoLinux distribution is the latest Linux distribution to shut down.
-
What Open Source Pros Look for in a Job Role
Learn what professionals in technical and non-technical roles say is most important when seeking a new position.
-
Asahi Linux Runs into Issues with M4 Support
Due to Apple Silicon changes, the Asahi Linux project is at odds with adding support for the M4 chips.
-
Plasma 6.3.4 Now Available
Although not a major release, Plasma 6.3.4 does fix some bugs and offer a subtle change for the Plasma sidebar.
-
Linux Kernel 6.15 First Release Candidate Now Available
Linux Torvalds has announced that the release candidate for the final release of the Linux 6.15 series is now available.
-
Akamai Will Host kernel.org
The organization dedicated to cloud-based solutions has agreed to host kernel.org to deliver long-term stability for the development team.