DEFCONConference
4 HN recommenders · recommended in 9 months, 2019–2026
46:04 · 86K views · Oct 22, 2018
Christopher Domas presents research at DEF CON 26 showing a hidden alternate instruction set and undocumented hardware backdoor in some x86 processors, found on a third-party CPU. He uses it to ask how feasible wider hardware backdoors are.
HN regulars treat Domas as a favorite hacker and bring this talk up in any discussion of CPU backdoors, hidden instruction sets or processor security.
10 comments from Hacker News
I cannot wait for the accompanying Black Hat talk. Christopher Domas is one of my absolute favorite all-time hackers. He does such a fantastic job of explaining his work. Some of my favorite talks of his: - Psychological Warfare in Reverse Engineering [LINK] - The MoVfuscator [LINK] - Hardware Backdoors in redacted x86 this video
These links don't work for me, but the videos are on YT: - this video - [LINK] And yes, they are spectacular.
Holy shit, Christopher Domas is back. I remember watching his Defcon talks on x86 shenanigans[^1][^2] and being amazed at what he's been able to discover. Then he got whisked away by Intel and now drops this. I'm excited. [^1]: [LINK] [^2]: this video
This guy now works for intel: DEF CON 26 - Christopher Domas - GOD MODE UNLOCKED Hardware Backdoors in redacted x86 this video This is one of many amazing videos this guy did before they hired him.
You are taking these ideas into crazy places! Fun to think about. Given this context, I have a few thoughts: Contemporary processors may be interesting when simplified some. Your projects make me think about the Zachtronics games. [LINK] That is an assembly language game with surprising depth. People, who play it seriously will learn quite a lot. Using older hardware in tandem with current is a lot of fun. The terminal, for example, still does exactly what it was designed to do and is still useful today. A C64 has a user port for this kind of thing. Apple 2 computers saw all manner of expansion cards capable of data capture, control, computation... making ones own card with a PIA was a standard type project, just as connecting a circuit to the user port was. BASIC was often enough for many basic controls, say regulating temperature, or turning things off and on based on time, or other data states, assembly language brought more of the speed possible, and with more speed, we get more posibilities. Take one bit wired to a speaker. That is what the Apple and IBM PC shipped with to make sound. The PC had a spiffy timer to bang out notes, and the Apple had nothing but a toggle. Speaker on, or off. Here is where the fun part was back in the day: At first, it seems useless. Access an address and the speaker pops out. Do it again, and the speaker pops in. One can type this right into the computer with a BASIC POKE statement, or the monitor by address and watch the speaker change stat