A buffer overflow can allow hackers to access your system in unexpected ways. (Photo credit: Lars Kienle)
A buffer overflow is an exploit used by a hacker to force a system to perform actions not intended by the programmers. To understand this concept, we first need to understand what a buffer is.
A buffer is a place where data is stored. A common example of this would be a login/password text box on a website. For our purposes, let’s assume that the text box is expecting a password of 12 characters or less. If a malicious hacker can input a formula that the programmer didn’t account for that could result in many more than 12 characters being entered into that text box, those extra characters would spill over into the surrounding memory, causing unintended side effects. This type of exploit can be used by the bad guys to gain access to hidden information on the system which could compromise and even change the operations of that computer/server. Without the proper controls in place, the extra information (overflow) is inserted into the computer memory, causing the computer to blindly run new instructions.
The simplest method for preventing buffer overflows is to use a programming language that does not allow for them. While C allows for buffer overflows, other languages such as Java, Python, and .NET do not require special changes.
Buffer overflows can represent a serious vulnerability to your systems. It is important to check your code for these vulnerabilities and ensure that you are mitigating risk from these types of attacks!