
Linux Reverse Engineering CTFs for Beginners - 1nvalid
https://osandamalith.com/2019/02/11/linux-reverse-engineering-ctfs-for-beginners/
======
codesuki
For some great fun and learning I recommend Googles beginner CTF.
[https://capturetheflag.withgoogle.com/#beginners/](https://capturetheflag.withgoogle.com/#beginners/)

The last thing that glued me to my seat like this was maybe 10 years ago. Good
to have had that feeling again. Hope they make a 2019 version! :)

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stuxnet79
As someone who is not very knowledgeable about the field, I find reverse
engineering fascinating. One thing I've been curious about is the economics of
the security industry and the role reverse engineering plays in it.

To my novice eyes it seems that reverse engineering is more of an academic
exercise and I don't see any direct ways to commercialize that skillset. How
do you make a living doing this? Are you essentially paid a stipend to conduct
fundamental research (finding zero days) that is inherently risky (no exploits
= no return on investment)?

~~~
throwawayre
There are plenty of money to be made, just not in the way you typically do
with other kinds of software. For example, a company named Bossland reversed
many popular games and made bots for those. Their most recent effort was
Pokémon Go. Nobody has reversed the newest versions of Pokémon Go and I
believed you can make millions off it if you play your cards right.

~~~
rnotaro
Not really ethical though.

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saagarjha
> Up to how many characters does it loop? Here’s how I found it. Basically,
> our password must be of 7 characters in length.

One way to see this without running the program is look for where $ebp-0x24 is
set:

    
    
      1210: c7 45 dc 07 00 00 00  mov    DWORD PTR [ebp-0x24],0x7

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archgoon
I recommend anyone who is attempting to do a ctf reversing challenge to
checkout r2.

[https://rada.re/r/](https://rada.re/r/)

It's a free and open source set of tools specifically for reverse engineering.

There are some commercial options as well such as HexRays IDA Pro (probably
the defacto standard tool) and binary ninja.

~~~
brunoqc
Do you use Cutter or the CLI?

~~~
archgoon
I use the CLI when I use it (mind you; it's largely for CTF style questions
most of the time).

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leibnitz27
I'd definitely recommend trying the flare-on RE challenges - they do a new
compo every year, and the previous compos, with helpful hints / solutions, are
available.

[http://www.flare-on.com/](http://www.flare-on.com/)

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alasdair_
Can anyone recommend a guide for network security CTFs, ideally including how
they are typically set up and common tools? It would be great to know what is
typically allowed to be done in such contests and what is explicitly against
the rules.

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gricardo99
For Beginners, I'd begin with defining "CTF".

I don't see that defined anywhere in the article.

From some googling, I guess it's a "Capture the Flag" challenge? It's worth
stepping back and explaining that general concept.

~~~
mlevental
this is now an hn trope (complaining about some jargon in the title).
newsflash the meaning of the title isn't "Linux reverse engineering for
beginning humans that don't know anything about the universe, language, or
electricity" because then you'd need to define Linux and engineering as well.
the meaning of the title is always "____ thing for people that know a little
about ____ thing but not everything". i think it's a very reasonable
assumption on the part of the author that the only people he/she is
accountable to for the intelligibility of such a title is someone who searches
out the article, since after all this isn't about regattas nor is it assigned
reading in some kind of primary education course. this kind of bad faith
reading of these articles is beyond worthless (and certainly doesn't merit a
comment). what I can't for the life of me understand is why hn is like the
epicenter of this kind of pseudo-critical engagement with media - neither
Reddit not Facebook has these kinds of comments nearly as often (nor the
closely related "... didn't read after ___" where ___ is a word in the first
sentence). my hypothesis is that it has something to do "intelligence
signaling" because people wrongly believe that being critical is an indicator
of intelligence.

~~~
JesseWright
While some people might post such comments for the sake of "intelligence
signaling", the GP seemed to not know what "CTF" meant. I think he offered a
fair and simple criticism, and I found your comment needlessly harsh and
presumptuous.

Even if some people post comments like that as a trope, some - if not many -
post them sincerely. I think the original criticism makes perfect sense: an
article for beginners might better benefit its readers if it offers just a
simple sentence or even link that briefly explains what the topic is before
delving into its details. I personally have read a number of articles where
I've encountered this problem, despite my familiarity with the given topic.

Also, I think it benefits the HN community at large if we try our best to read
people's comments in a positive light, within reasonable, and encourage giving
and receiving constructive criticism from one another.

