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Can a buffer overflow attack work without EIP?
Unfortunately there are some things standing between you and a successful buffer overflow attack: You don’t really know where the EIP is located, without the address of the EIP register then you could not craft the string to overwrite the address with an address of your choose.
How to understand buffer overflow beyond simple stack overwrite?
I have recently embarked on the task of understanding Buffer Overflows beyond simple Stack Overflows and I figured the best way to go about it was to go back to the start, recover Stack/Assembly principles. Quickly recover simple Stack Overflows and then begin writing a blog post for each relevant area that I want to learn in greater detail.
What is buffer space and what is EIP?
For the scope of this tutorial, we really need to be concerned with buffer space and the EIP. Buffer space is used as a storage area for memory in some coding languages. With proper input sanitation, information placed into the buffer space should never travel outside of the buffer space itself.
What happens when EIP is overwrite with noise?
If it happens that the EIP register is overwrite by the A’s, then you altered the address to return for the execution of the next instruction, obviously if the EIP is overwrite with “noise” you will have an exception raised and the program will stop.
How are the parameters saved in a buffer overflow?
The Function Stack is created, inserting the register EBP in the stack to set the anchor The parameters are passed as a memory address to EBP+8, EBP+12, etc… The Function is called and the returned data is saved in memory and pointed by the RET variable on the position EBP+4
What are the basics of buffer overflow exploitation?
Author: mercy Title: Basic Buffer Overflow Exploitation Explained Date: 30/10/2002 oO::BASICS::Oo A starting point for this tutorial requires the readers to have a simple understanding of the C programming language, the way the stack and memory is organised, and asm knowledge is helpfull though not essential.
Where does the EIP point in the program?
EIP is the Extended Instruction Pointer it is a read-only register and it contains the address of the next instruction to read on the program, point always to the “Program Code” memory segment.