Intro to Buffer Overflow

A buffer is simply a space in memory designed to hold a fixed amount of information. This information can be a string. An example of a string is a sentence like, “Hello, world!

can occur in program language like C,C++ and IOT/Embed system

popular CVE : CVE-2017-12542 , CVE-2021-315

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main types of exploits:

1. 0-Day Exploits – Target unknown vulnerabilities that haven't been patched.

2. N-Day Exploits – Target known vulnerabilities before they are fixed.

Exploits are categorized into:

• Local Exploits: Require local access to escalate privileges.

• Remote Exploits: Work over a network, often using buffer overflow techniques.

• DoS Exploits: Disrupt services by crashing software or overloading resources.

• WebApp Exploits: Target web applications via command injection, SQL injection, etc.

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CPU Architecture

• Memory

• Control Unit

• Arithmetical Logical Unit (ALU)

• Input/Output Unit

von_neumann3.webp

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EBP → refer to bottom of stack

ESP → refer to Top of stack

Stack →work on LIFO (last in first out)

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how code execute

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Debugger → tool like burp suite work between computer and server which can edit code