Analysis and Prevention of buffer overflow attacks

Zhao youen1Zhou shoujun2

(1.Department of Computer Science and Technology, Shandong Economic University, Jinan250014)

(2.Thermal Engineering College, Shandong Construction Engineering University, Jinan250014)

AbstractYesBuffer overflow attacks are the most common forms of attacks, which occupy the vast majority of remote network attacks and represent a type of extremely serious security threats.FromCERT/CC (Computer Emergency Response Term/Coordination Center)Buffer overflow attacks56.76%Above.This article mainly introduces the principle, classification and intrusion methods of buffer overflow attacks, and puts forward corresponding preventive measures.

Keywords Buffer ZoneOverflowPrevention

Preface

A buffer is a continuous memory that the user applies for on the computer when the program is running. It stores data of a given type. Buffer overflow refers to a common and harmful system attack method. By writing content beyond its length to the buffer zone of the program, the buffer overflow is caused, which destroys the program stack, turn the program to execute other commands to attack the program.More seriously, buffer overflow attacks account for the majority of remote network attacks, which can make an anonymousInternetUsers have the opportunity to gain some or all control of a host! This type of attack makes it possible for anyone to gain control of the host, so it represents an extremely serious security threat.

1.Buffer overflow attacksAnalysis

The purpose of a buffer overflow attack is to disrupt the functions of programs with certain privileges, so that attackers can gain control of the program. If the program has sufficient permissions, then the entire host is under control. Generally, attackers attackRootProgram, and then executeExec (sh)To obtainRootOfShell. To achieve this goal, attackers must achieve the following two goals: arrange appropriate code in the address space of the program; through the appropriate initialization of registers and memory, let the program jump to the pre-arranged address space for execution.Based on these two targets, buffer overflow attacks can be divided into the following3Class.