How They Hack: Simple Buffer Overflow

I bashed this video together to show you the loose concept of a buffer overflow and how abusing inputs can enable an attacker to execute code or change the behaviour of a program in a noteworthy way. This example is very simple compared to more modern examples which are covered in my other videos.

[@JamesLyne]

Hey everyone, this is one of a series of 7 videos that cover basic buffer overflow concepts. They were used for me to answer a specific question I was asked but thought they might be more generally helpful. This is a very rudimentary example compared to what happens today, but it is a good place to start.

[@alicandonmez6748]

Nice explanation, more videos on other type of attacks please :)

[@tryingtocorrect]

Excellent explanation. So easy to understand, and now can think more complicated situations what hacker could do.

[@feo130]

Awesome explanation, thank you!

[@rameshpandita1922]

This was explained perfectly thank you so much 💓

[@praveshshukla3940]

this is very helpfull and interesting, but what if the user running program in as non-root user, then their this won't be possible. and the next things please explain-- how if non-root user saw segmentation fault (core dumped), then how to see the detail as where the core is dumped .

[@narimanmortezaei5888]

char array is defined first and then the passcheck variable. shouldnt it define the array first and and then the passcheck in stack (from lower memory addresses to higher we have passcheck and then array)? or am i missing something ?

[@unboxer2487]

That is actually what I am thinking as well. Have u figured it out why it is so?

[@darshank3012]

excellent... thank you

[@nikhilfinework354]

You are very underated

[@mamakfm7b929]

watching this in 2024 almost ,thank u

[@nm_9_]

same

[@dilrajdhillon9231]

sir, what would have happened if we would have put if(passcheck==1) instead of if(passcheck)

[@unboxer2487]

Just try it.

[@thenextbigthing1393]

Then it would just show "you fail" I guess.

[@neunzehnvierundachtzig]

Fail cause anything other than 0 is true. but you're doing specific Boolean comparison here.

[@omarAhmed-wt8kx]

good representation

[@ancestrall794]

Thanks a lot

[@praveshshukla3940]

And sir can you please give the detail about what these means, atleast at an abstract level would be fine: root:!:17156:0:99999:7::: daemon:*:17001:0:99999:7::: bin:*:17001:0:99999:7::: sys:*:17001:0:99999:7::: etc,etc

[@tsunningwah3471]

bbbbbbbbb s

[@3hustle]

💻 The video explains the concept of buffer overflow in computer security using a simple C program as an example. 00:14 Buffer overflow is a common security vulnerability that allows attackers to execute unauthorized functionality. 00:14 The video demonstrates a simple C program with a vulnerable gets function and a storage area for characters. 01:02 The gets function captures user input and can lead to potential security exploits. 01:45 The concept of buffer overflow extends to modern code and is still a relevant security concern. 02:26 ⚠ The video discusses the potential security risk of buffer overflow in a program and its implications. 02:59 Buffer overflow can occur when too much information is provided, leading to overwriting of nearby memory. 02:59 The program functionality allows access to sensitive files if the correct password is guessed. 04:33 The lack of stack protection in the program makes it vulnerable to exploitation. 05:08 💻 The video discusses the impact of buffer overflow and the importance of bounds checking in preventing security vulnerabilities in software development. 05:20 Buffer overflow can make things simpler for attackers, like in the old days. 05:20 A longer input string can lead to overwriting memory and executing unintended functionality. 05:46 Failing to do bounds checking can be extremely beneficial to attackers. 07:00 Developers should pay attention to bounds checking and avoid older, less secure functions.