How Do Buffer Overflow Attacks Work?

Overflow Attack - Blog

In some cyberattacks, the buffer overflow vulnerability is exploited to breach a system. Using a term like a buffer, this is a generic word describing an environment where one can store temporary things to avoid the lag between input speeds or output speeds.

When programming computer data is put into software buffers for processing or retrieval, a “software buffer” is simply a physical memory area that can be accessed using the program’s programmable memory and stored on a specific drive.

Buffer overflow is a problem in which computers write data into the buffer but then burst into the boundaries of other buffers, corrupting or overflowing it.

Imagine a container that can hold 8 liters of water in it and suddenly more than 10L of liquid are poured into it. With no room for more liquid, the contents overflow the container. Buffer overflows are a similar concept based on the same basic principles.

How do buffer overflow attacks work?

A hacker exploits memory overflow issues in a system. This affects the execution route of the application, triggering responses that damage files or expose sensitive information to other parties.

A buffer overloaded with data causes a data overflow into adjacent storage. This vulnerable vulnerability can lead to crashes in the system. C++ can cause buffer overloading.

A buffer overflow is the most widely used type for computer software vulnerabilities but is still used for cyber attacks. The use of compiler tools, safe function patched web servers, and scan software can help reduce the chances of buffer overflows.

Is C vulnerable to buffer overflow?

Several programming languages can have buffer overflow issues more than others. C++ and C# are widely used and vulnerable languages. Windows, Mac OS, and Linux use the languages of these languages. Modern languages like Java Perl and C# include features for reducing buffer overload but they don’t stop it completely though.

Choice of languages Assembly and C++ are common programming languages that are vulnerable to buffers to overload, these languages allow directly accessing the memory and are not strong typed.

Vulnerable programming languages

C++ is a two-language that has a high potential for buffer overflows due to a lack of built-in safeguards to prevent the rewriting of data in the memory. Windows, Macs, Linux, and Linux use coding in C / C++. Languages including C#, JavaScript, and Perl have safety features that minimise potential overloaded buffers.

Attackers exploit a buffer over-flow problem to overwrite a program’s memory. Changing the executable paths triggers the response that damages files and/or divulges confidential information.

A malicious attacker can introduce additional malicious code to a system to gain access to information technology systems, or eavesdrop on existing data. During a hacker’s attack, he could intentionally send in data that the buffer can’t keep and delete the areas that hold executable code and replace it on his own. A hacker can overwrite a pointer (a pointer in a memory object) and redirect it to an exploit payload to gain control.

What’s a buffer?

A data buffer is a piece of physical storage space used to temporarily store data during moving between locations. The buffers usually have RAM storage. Computers often use buffers for improving their performance; most modern hard drives use this feature to access information easily; many websites use buffers.

Similarly, buffering is often used for streaming online videos so that interruptions are avoided. The video player downloads 20% of the video at once into the buffers and streams it to the buffer.

Notable examples of buffer overflow attacks

It should be noted that buffer overflow is a common security vulnerability and has long since become a common problem. The massive buffer overflow attack caused one of the largest data breaches of all time.

Morris worm 1988 – The Morris worm is an online computer worm, the first to receive widespread media attention in the United States. It has a bug with the Sendmail, rsh/rexec UNIX that causes buffer overflows. Between 1998 and 2000, Morris worms were able to be emitted onto nearly 60 million machines.

Buffer overflow vulnerabilities and attacks

This is a problem with buffer overflow that dates from the early days of interactive computing. Certain programming languages are at risk of buffer overflow as they don’t provide bound checks or safeguards for accessing or deleting data.

Many higher-level languages including Java, Python, and C# built into it to help prevent buffer overflow. Many hackers use buffer overflow vulnerabilities as a way for them to compromise a targeted application or system.

How do attackers exploit buffer overflows?

An attacker may intentionally input data to a program that forces the program’s buffers to be smaller or overwrite portions of memory that are not enough to be stored. When the memory configuration in the program is properly defined, the attacker may accidentally overwrite portions that contain executable code.

The hacker then may modify this code by creating a program whose code is radically changing the program’s intended function. There are different forms of buffer overflow attacks.

Stack-based (Stack overflow attack) / Stack overrun attack

The stack contains data in first-out first-in form. The memory has a constant space in the memory used for organising the information of function calls such as function parameters, function locale variables, and control information such as instruction and frame information.

Usually, a stack is left empty until it needs input from a user to create a login account. Upon this level, the program adds a memory address, and the input is put onto the stack. When stack processing occurs, inputs are received from the user to the address indicated by the program. However, scuffs are limited in size.

Integer overflow attack

In some programming languages, integers have a limit on the number of bits that will be used. If this size is exceeded the result will result in errors, or it will result in a wrong result at the limit of the integers.

The underlying attack occurs when an integer is used for calculating the result of the calculations that exceeds its maximum size. Typically the data in 192 is stored in 8bits memory. The answer 256 cannot fit in the stored memory because this number requires nine bits.

Heap-based overflow attack

The buffer overflow occurs when the heap contains memory structures that store dynamic information for a given memory. Often programmers can use this heap to assign memory with a size that is unknown when compiling when memory is too small, or it will be used across functions. A heaping attack floods the memory of a process or program. Heaps are hard to exploit and are less likely than buffer stack attacks to attack websites and applications.

Buffer overflow vulnerability vary. This means there are different ways to mitigate buffer overflow attacks. Developers must practice writing secure code to avoid memory access errors

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