The paper’s I’ve written over the years.
Cheating the ELF: Subversive Dynamic Linking A paper explaining the ELF format and how to abuse the dynamic linker to access library code.
More ELF buggery Presented for historical purposes only. Some code I released for people to copy when they were implementing the dynamic linker’s resolv() functionality.
Armouring the ELF: binary encryption on UNIX platforms My first article for Phrack. Describes some techniques for encrypting binaries on Linux. This was an important issue at the time as hacker groups were trying to stem the leak of private exploits. There was also the problem of exploit code being discovered in the wild and the bugs dying. This was an attempt to lock down access to the exploits, as well as the information (i.e. the vulnerability) contained within the exploit. My implementation used the subversive linking technique from the previous paper.
The Art of Defiling: Defeating forensics analysis on Unix file systesm The ur-text of anti-forensics. Few people seem to have understood what was actually in here. After the publication of this article I was forced to resign from @stake. The techniques in here are still valid against some modern forensics tools. The core take aways though should be the basic strategies of anti-forensics.
Bypassing 3rd party Windows buffer overflow protections This paper explores a large number of ways to bypass HIPS systems that are bolted onto an operating system, rather than baked in. Mostly techniques for skipping the hooks which transfer execution into the HIPS logic. This article was written by myself and Eugene, with the NT syscall shellcode provided by jamie butler. We’d all done similar research, so decided to collaborate on a paper. At the time, Eugene and I both worked for HIPS companies so we decided to publish anonymously to avoid any problems.
FIST FIST FIST Its all in the wrist This was my final anti-forensics paper. I don’t believe there has been anything which advances the core theory of anti-forensics beyond this paper. I now know that I was developing counterintelligence theory from first principles. Slow going. This paper deals primarily with in memory execution techniques for Linux. It covers some important anti-forensic principles as well, in particular minimizing the operational fingerprint.
Userland Exec A quick little paper for a quick little project. At the time someone had posted an implementation of userland exec to bugtraq which simply copied a binary into the stack and jumped to the entry point. Mark Dowd asked me how this would be done “properly”, and in the process of explaining it to him, I decided it would be easier to just write a PoC. So, that weekend I banged out a PoC of ul_exec() and wrote up a paper on how it worked. It was a useful technique for anti-forensic tools as well as it enabled pulling a program out of an encrypted data store and executing it without creating a clear text version on disk.