In early 2024, it was discovered that a software backdoor had been intentionally inserted into beta versions of the xz utils library, an open-source utility which is extensively used in Linux computers around the world. A software backdoor allows a remote user to bypass normal authentication within a computer, from there gaining access to privileged information. In the case of the malicious xz utils library, the backdoor inserted itself into the sshd process, which is used to make remote connections to the outside world and is thus extremely vulnerable to attack. The attack came frighteningly close to succeeding and was only discovered when a curious software developer noticed that beta builds of the xz utils library were acting slower than normal during testing. This incident highlights the inherent risks associated with allowing anonymous users to contribute to open-source software, while simultaneously exemplifying the security benefits of allowing for transparent review of code which is ubiquitously run.
