Good work with the quick and easy to follow explanation of a buffer overflow. I've seen them explained in so many different ways and this was concise and to the point. Great work John!
Love this. So simple yet so effective. Whilst consuming most of the videos explaining this topic I am left thinking I wish there was a 3x or 4x speed. Not with this though. Thanks for a super quick explanation of how to get to it, in this example at least and actually get the overflow done.
I am see that is trying to be myself and is not has been watched at 4 times in this subscription and membership I joined in the last couple of days alone thanks John
Amaizing, why others cant explain the bufferoverflows like you? you make this so easy... hours of theory for nothing, in less than 10 minutes you explained id...
It's the address of the start of the secretFunction. John is overflowing the buffer and overwriting the return address on the stack so that the program, instead of simply exiting, returns to the secretFunction. The reason ';\x85\x04\x08' is used is because this system is little-endian (en.wikipedia.org/wiki/Endianness#Little-endian tldr: bytes are in reverse order). The ';' may throw you, but that's simply bash printing the actual ASCII value of '3b' (man7.org/linux/man-pages/man7/ascii.7.html). Hope that helps!
![Patching Binaries with Pwntools | BE QUICK OR BE DEAD 2 [29] picoCTF 2018](/img/1.gif)
Watching your buffer overflow has explained more than the hours of theoretical videos I've watched...
Thank you.
Exactly this.
@@cwlancaster979 approve
Ive never seen a BO explained in less than 10 mins... Great job!
kek, that's john
Actually this the best simple detailed explanation for BoF I had ever seen ! Good job
Thanks so much, I appreciate all the kind words! Thanks for watching!
Good work with the quick and easy to follow explanation of a buffer overflow. I've seen them explained in so many different ways and this was concise and to the point. Great work John!
Hey thank you, I am really happy to hear that! :D I appreciate the kind words, thanks again!
Hands down best BoF video to the point I've come across! You sir are a savior. Thank you
Love this. So simple yet so effective. Whilst consuming most of the videos explaining this topic I am left thinking I wish there was a 3x or 4x speed. Not with this though.
Thanks for a super quick explanation of how to get to it, in this example at least and actually get the overflow done.
This is the best example I have seen for a BO
Thank you so much, and thanks for watching!
@John Hammond really love you and your content
that is actually fantastic, Prof. Hammond !
better way to learn BOF is just watching CTF videos :D . tks for making this
Thanks for the kind words! :D
I am see that is trying to be myself and is not has been watched at 4 times in this subscription and membership I joined in the last couple of days alone thanks John
im struggling with bof but damn this made it look easy. thanks!
Amaizing, why others cant explain the bufferoverflows like you? you make this so easy... hours of theory for nothing, in less than 10 minutes you explained id...
Awesome explanation. Thank you!
Nice video and well explained..
Thank You!
oh that was easier than i thought lol
Thanks for the video =)
WOWW just wow!!
Wooh!!! Thanks
banger video
Good to know another way to solve this CTF. I've used objdump and found how many bytes is allocating for buffer.
like the title a alot
Ugh, I was so close to solving it myself...
tysm
Hi John
Is it possible to use GDB there and find the specific size of the buffer to avoid doing trial and error trying to find where the buffer is overflowed?
j'ai rien pigé, tu m'as perdu direct xD
I wonder if you can use GDB on that challenge...
Can anyone explain to me about the 0x0804853b and ;\x85\x04\x08 ? What are they called and what are they used for ?
It's the address of the start of the secretFunction. John is overflowing the buffer and overwriting the return address on the stack so that the program, instead of simply exiting, returns to the secretFunction. The reason ';\x85\x04\x08' is used is because this system is little-endian (en.wikipedia.org/wiki/Endianness#Little-endian tldr: bytes are in reverse order). The ';' may throw you, but that's simply bash printing the actual ASCII value of '3b' (man7.org/linux/man-pages/man7/ascii.7.html). Hope that helps!
Pourquoi n'avons nous pas besoin d'instruction JMP ou CALL ?
Can you do more python videos please John
can you please share your story how can you become a hacker
This is a good idea! Absolutely, I will definitely share my story in a video. :)
John Hammond ok..I am excited