Taking the opportunity to ask: are there nice recommended resources for a beginner to start with reverse engineering (ideally using Ghidra)? Let's say for an experienced developer, but not so experienced in reverse engineering?
I guess one issue I have is that I don't have good ideas of fun projects, and that's probably something I need to actually get the motivation to learn. I can find a "hello world", that's easy, but it won't help me get an idea of what I could reverse engineer in my life.
For instance I have a smartspeaker that I would like to hack (being able to run my own software on it, for fun), but I don't know if it is a good candidate for reverse engineering... I guess I would first need to find a security flaw in order to access the OS? Or flash my own OS (hoping that it's a Linux running there), but then I would probably want to extract binary blobs that work with the buttons and the actual speaker?
Allow me to shamelessly plug my blog, I have been (very slowly!) re-visiting microcorruption and writing up the solutions in a tutorial-esque fashion.
https://lovesexsecretgod.com
> Taking the opportunity to ask: are there nice recommended resources for a beginner to start with reverse engineering (ideally using Ghidra)? Let's say for an experienced developer, but not so experienced in reverse engineering?
The good news is that there has never been MORE resources out there. If you want to use this learning expedition as an excuse to also build up a small electronics lab then $100 on ali express to buy whatever looks cheap and interesting and then tear it apart and start poking around to find where the firmware lives. Pull the firmware, examine it, modify it and put it back :)
This guy has a discord server with a specific "book club" section where they all choose a cheap $thing and reverse engineer it: https://www.youtube.com/@mattbrwn/about
I can't help much with "traditional" app/software RE work, sorry.
Oh, it feels like it may be what I want! Find some cheap electronic device and hack it!
Thanks a lot!
I would also suggest spending a few minutes to set up an mCP server with ghidra once you've learned the basics of navigating and working inside of ghidra.
Turns out that frontier grade llms are absolutely fantastic for extremely advanced static analysis. If you go one step further and manage to get your firmware running inside of an emulator or other place where you can attach GDB... Then putting an mCP server on that as well unlocks so much insane potential.
Would that include free use LLMs. I assume getting into something would be tricky if you are assuming they're going to drop several hundreds of tokens a month on it.
I feel like the tendency for people to assume others have nearly $500 or so of credits on their AI to blow every month is kinda crazy.
Reminds me of the "just get Netflix, Prime, etc." ending up with a $100/m bill.
I started reverse engineering at 13 with an IDA Pro of questionable provenance - at that time, I found it quite difficult.
One thing which really helped me (and I wholeheartedly recommend) is to write simple programs, run them through the compiler and then in the disassembler. It really helps build a correspondence between program structure and its object code.
Eventually, you can make it even more fun and challenging by stripping debug symbols and turning on compiler optimisations.
Happy reversing!
The Nightmare Course [1], so named because someone with that skillset (developing zero-days) is a nightmare for security, not because the course itself is a nightmare, and Roppers Academy [2] are both good for learning how to reverse engineer software and look for vulnerabilities.
The nightmare course explicitly talks about how to use Ghidra.
1: https://guyinatuxedo.github.io 2: https://www.roppers.org
The first is certainly interesting, but it won't help you develop 0day. I would think of it like more of a collection of fun puzzles and esoterica. For example all the heap unliking/metadata attacks and House of X stuff is pretty antiquated. These will help you win ctfs but are certainly not a prerequisite or even all that relevant to contemporary vuln research. Most of the public research I see is probably at least a year behind the current meta (and I expect the public internet will only grow more quiet over time)
Finding something with symbols will help a lot. Symbols end up getting left in Linux and macOS builds fairly often.
The reverse engineering I've learned has generally been to fix something that has annoyed me - for example I reverse engineered part of RCT3 to fix mouse input with high poll rates and allow for resizable windows [0]. Certainly easier to approach than trying to get into a closed device since you can attach a debugger.
[0] - https://mastodon.social/@benpye/109261545643008493
If you are into the book, I would recommend The Ghidra Book from No Starch publisher https://nostarch.com/ghidra-book-2e.
The book is designed for beginner and advance users.
Somewhat unconventional (and i'm not really a seasoned reverse engineer so take it with some salt) but I started by hacking old video games (nes, gameboy, arcade.. that kind of thing). You could start with making basic action replay RAM cheats to e.g. give Mario infinite lives, then you can use breakpoints, the debugger, and a 6502 ISA reference to edit instructions and make ROM patches.
from then you can use things like Ghidra (which supports a lot of those old CPU arches) for more advanced analysis and make the game do almost whatever the hell you want if you have the patience.
I think a lot of the skills will transfer quite well (obviously not 1:1, you will need to learn some things) to the more employable side of RE if that's what you're interested in
Thanks! I have been "hacking" with games in the past (getting infinite lives and such) or bypassing some licence check (back then it was with OllyDbg).
I guess I'm struggling to transfer that to "real-life" scenarios. Like getting something useful out of reverse engineering (getting infinite lives is interesting to see that I can tamper with the game, but it's not exactly useful).
Honestly unless you're working in low-level fields, such as embedded hardware, or optimized code generation, those are real-life scenarios!
(Thinking more of license-checking, and serial-number generation rather than infinite lives.)
So a couple things. Bruce Dang’s book, while a little old, is still a great spot to get started. Another great book is Blue Fox by Maria Markstedter for ARM. From there, finding small binaries and just trying to get the “flow” is a good next step, for me this is largely renaming functions and variables and essentially trying to work the decompiled code into something readable, then you can find flaws.
So for the second thing, pulling the data off chips like that typically involves some specialized hardware, and you have to potentially deal with a bunch of cryptographic safeguards to read from the chip’s memory. Not impossible though, and there are not always good safeguards, but might be worth checking out some simpler programs and working up to it, or learning some basic hardware hacking to get an idea of how that process works.
Interesting! Yeah maybe my first step is on the hardware side, which I guess is what is blocking me right now.
https://pwn.college has really good modules/dojos that cover a bunch of reverse engineering concepts.
Find an old piece of software you care about that is broken somehow, and abandoned. Most of my friends use these types of tools to reverse engineer abandoned MMOs and remake servers for them.
That's very deep water to dive into. I suggest something simpler, like an ancient irc client that asks you to sign up, or an archive extractor.
Well I didnt mean dive into an MMO right away, but yes I recommend smaller programs.
I personally learn best by doing which is why I love learning with LLMs. They're going to be wrong a lot, and give bad advice, and do things in silly ways. I learn well from the process of working with them, seeing them fail constantly, then learn the tool yourself by researching what it's doing wrong to fix it. I just attempted to use Ghidra to reverse engineer the game Shenmue from Dreamcast. I was previously unfamiliar with Ghidra and I mostly did it as a learning exercise, but it wasn't really the right tool for the job. However the project itself made lots of progress without it:
https://www.newyokosuka.com/
You can start here to learn reverse engineering.
https://beginners.re/
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Since we're judging each other, I'm genuinely wondering how bad you are at making friends. I mean, non-LLM friends. Relatives don't count.
Im neurodivergent as hell, so good at all. But I also don't really require friendships, as people interactions are very draining on me.
> Im neurodivergent as hell
Well that may explain it, then, thanks for letting me know.
I realise that my question was not super clear because... well I didn't really know what to ask :-). I was just trying to engage in a human interaction. Say I am at a party with friends and strangers, and when I get introduced to a stranger, they say "I am a professional reverse engineer". Because I find that interesting, I will start asking questions. And I may well start trying to explain what I find interesting, giving the expert an angle to start talking about it.
Of course I could just go home and read about reverse engineering. But at that moment, in that party, I want to enjoy a discussion about it with a human being. Part of the experience is that I get to hear what some other human thinks about it.
I am not there for a formal course, I am there to listen to what a human being has to say about it. And obviously an LLM cannot do that job :-).
God forbid someone pose an interesting question on a discussion board.
You were rude but I understand what you mean. People can obviously Google "reverse engineering tutorial" or something similar. And certainly "what are good resources for X" can be a way to signal interest in something, get people to respond, and not necessarily do anything about it. But I think the most charitable interpretation of that question is they want a group consensus for the best place to start, since Google might return a heavily promoted site that had deprecated info. I remember years ago people hated "cplusplus.com" because out of a volume that is the size of a textbook, it had a few bad examples. So instead they promoted cppreference. (For learning C++).
I think we should conclude people want to maximize learning while minimizing wasted time, hence they ask for the "best resources". Even though the question seems tiring at times (when I was on reddit I heard this constantly, and cynically projected that very few people actually used the resources they requested. But I solved this problem by quitting/getting banned from Reddit and never looked back).
> can be a way to signal interest in something, get people to respond, and not necessarily do anything about it.
I can explain my intent, since I asked the question :-).
"Signal interest in something in the hope of starting a discussion with people who share that interest and may have interesting stories to share".
I loved IRC for that. I could join a channel, ask a question and sometimes someone knowledgeable would engage in a discussion with me. Often nobody answered, but because IRC was "ephemeral", I could ask again another time, and another one, hoping to eventually find someone interested.
> I think we should conclude people want to maximize learning while minimizing wasted time
In my case (and I want to believe that in many other cases), it's really just that people (me, here) would like to have some human interaction about a topic.
I know how to learn, I was not asking about that. I was trying to start a conversation with humans, that's all.
> I was trying to start a conversation with humans, that's all.
Totally fair, and I'm sorry you got a hostile response.
My (very low-value) opinion is don't waste your time learning how exploits work. Yeah it's kinda neat seeing clever misuse of components. But there is very little upside to investing in that knowledge.
0. You look at old exploits and marvel at them for a while, but they are long ago patched and technically useless.
1. You waste a bunch of time looking for a sploit but don't find one.
2. You find one but nobody cares, you don't get street cred. The sploit is patched in the next release, and you don't get back your time spent finding it.
3. You find a sploit but all you get is a thanks from the billion dollar company, followed by a patch.
4. You create an exploit and use it maliciously or sell it to a criminal syndicate. you are a criminal. Or you get sued because it's a civil/copyright issue.
5. You find a sploit and other people treat you as a criminal even though you didn't do anything with it. You even intended to help.
6. You find sploits but still can't get a job as a white hat because other people who found more sploits got the job.
The only good outcomes are:
7. You found a very clever sploit and got a bounty for it.
8. You got hired in cyber security and get paid for sploits or countering them.
9. You seriously just love decoding machine instructions and find joy from making it do unintended things.
Overall, I think the risk/reward ratio is suboptimal for this field unless you go black-hat which is obviously fraught with moral and legal hazards.
I often wonder why on this forum of alleged hacker types, there seems to be such an impetus to push what all VC's are desperately bought into at the moment, whether it be crypto, or AI nonsense.
Oh wait... Right.
Asking for resources or asking "does anyone know where I can start?" Followed by a description of "here's where I'm at" has been table stakes for the uninitiated since time immemorial.
When I see "ask the LLM", all I hear is "prop up my investment portfolio".
To this OP in particular: try playing around with different binaries you already have source to, and using the RE tools to get a feel for their post compilation structure and flow; start by compiling with no compiler optimization. You'll want an understanding of what the structural primitives of "nothing up my sleeve" code reads and looks like post-compilation to build off of. Then start enabling different layers of optimization, again, to continue familiarizing yourself with output of modern compilers when dealing with fundamentally "honest" code.
Once you can eyeball things and get an intuitive sense for that sort of thing is where you jump off into dealing with dishonest code. Stuff put through obfuscators. Stuff designed to work in ways that hide what the actual intent of the code is, or things designed in ways that make it clear that the author had something up their sleeve.
It'll be a lot of work and memorization and pattern recognition building, and you'll have to put in the effort to get to know the hardware and memory architecture, and opcodes and ISA's, and virtual machines you're reversing for, but it will click eventually.
Just remember; odds are it won't make you money, and it will set time on fire. I cut my teeth on reversing some security firm's snake oil, and just trying to figure out why the code I wrote was acting weird after the compiler got done with it. (I have cursed at more compiler writers than about anyone but myself).
Then just remember that if someone got it to run, then it's gotta eventually make sense. The rest is all persistence on your part of laying bare their true, usually perverted motivations (generally boiling down to greed, job security, or wasting your goddamn time).
Would the world be nicer if that wasn't the case? Absolutely. I lived through a period where a lot of code wasn't "something up my sleeve" code. Now is not so much that time anymore. We've made programming too accessible to business types that now the interests of organization's at securing their power has a non-trivial distortion on how code gets written; which generally means user hostile in one way or another.
I happened to be at Amazon during Covid, and at a certain point during the hiring craze, I was doing like 3 interviews a week. I have interviewed probably close to 500 people so far in my career as software.
Even pre llm, there was a clear indicator of someone who was skilled at coding versus someone who was not. The big thing that differentiated people was curiosity. When someone is curious, they would go look stuff up, experiment, figure out how to build things by failing over and over again, and eventually they would figure it out, but consequently, they have learned quite a lot more along the way.
And then there were people that were just following instructions, who in interviews though that them following instructions was virtue worthy.
Nowdays, this is even easier to tell who is who, because LLMs essentially shortcut that curiosity for you. You don't have to dig through the internet and play around with sandbox code, you can just ask an LLM and it will give you answers.
This is why I specifically said if you are hesitant of starting with LLMs, you should learn how to learn first, which usually starts with learning how to ask questions.
Respectfully, I hope you don't judge the people you interview the way you judged me based on my question. You have no idea who I am, and surely not enough data to decide whether I know how to learn or not.
In my opinion, it is extremely important for the interviewer to realise that they are in a dominant position. Here, I can tell you what I think about how you judged me. If I was an interviewee, I may not be in a position to lose the job just because I told you that you are being rude.
Thanks! I appreciate the insights. I definitely don't expect to make money out of that, I really just want to learn and understand :-).
How interesting.
Anyway, I would recommend YouTube. Find a series you can follow along. Best of luck!