Asm

Linux.Nasty: Assembly x64 ELF virus

18 minute read Published:

Reverse Text Segment x64 ELF infector written in Assembly
Overview This code was originally published in the first issue of tmp.0ut zine - an ELF Research Group founded by me and a super talented group of friends in early 2021. This project was finished literally minutes before the deadline we set. Living on the edge! In general, it took me around a couple of months to complete it, most of the time was dedicated to its core infection routine since the auxiliary sections are common file I/O operations that I’m already familiar with.

Linux.Midrashim: Assembly x64 ELF virus

15 minute read Published:

PT_NOTE -> PT_LOAD x64 ELF virus written in Assembly
Overview My interest in Assembly language started when I was a kid, mainly because of computer viruses of the DOS era. I’ve spent countless hours contemplating my first humble collection of source codes and samples (you can find it at https://github.com/guitmz/virii) and to me, it’s cool how flexible and creative one can get with Assembly, even if its learning curve is steep. I’m an independant malware researcher and wrote this virus to learn and have fun, expanding my knowledge on the several ELF attack/defense techniques and Assembly in general.

Having fun with ANSI codes and x64 Linux Assembly

9 minute read Published:

Using ANSI escape codes with x64 Linux Assembly for command line fun
Overview How can one not find command line art amusing? Specially when we are talking about computer viruses and even more so when referencing MS-DOS ones. The 16 bit era gave us some of the most interesting computer virus payloads of all time, but achieving something like this today is not as “trivial” anymore. As Linux is my OS of choice, I wanted to find something that could get close to these MS-DOS fun payloads for my own modern viruses, and, while it’s possible to write directly to the framebuffer, I wanted to try something related to terminal emulators instead.