exploit

What is the Log4j Vulnerability?

Log4j is a widely-used library of log files for applications written in the Java programming language. It copies down everything that happens when a Java program runs. NPR spoke to Andrew Morris, founder and CEO of cyber intelligence firm GreyNoise, who described Log4j as “…a modular component that's used in many, many different kinds of software. And its job is... just basically recording things that happened and writing them to another computer somewhere else.” In December of 2021, Log4j was found to be vulnerable to remote code execution.

Put more simply, Log4j is a vulnerable logging library that allows attackers to take control of remote devices running Java software. This represents a severe security risk. Gadgets 360 reports that "the Apache Log4j Remote Code Execution Vulnerability is the single biggest, most critical vulnerability of the last decade," said Amit Yoran, chief executive of Tenable, a network security firm, and the founding director of the US Computer Emergency Readiness Team.

One of the most popular programs affected by this vulnerability is Minecraft. John Hammond, a noted cybersecurity researcher, recently posted a video showing how Log4j could be exploited in Minecraft, allowing a remote user to access the calculator of a system (proving that any other program or command could also be run). Tech Times posted an article detailing how Minecraft users can defend against this threat.

Unfortunately, Minecraft is not the only vulnerable software. Speaking to CNET, Nadir Izrael (CTO and co-founder of IoT security company Armis) said that “generally speaking, any consumer device that uses a web server could be running Apache. Apache is widely used in devices like smart TVs, DVR systems and security cameras. Think about how many of these devices are sitting in loading docks or warehouses, unconnected to the internet, and unable to receive security updates. The day they're unboxed and connected, they're immediately vulnerable to attack."

To mitigate this threat, users should continue to install all security patches and updates as soon as possible. As companies roll out patches to this vulnerability, it is important to stay on top of those updates!

What is Buffer Overflow?

A buffer overflow can allow hackers to access your system in unexpected ways. (Photo credit: Lars Kienle)

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!