XZ Utils backdoor
The malicious code is known to be in 5.6.0 and 5.6.1 releases of the XZ Utils software package. The exploit remains dormant unless a specific third-party patch of the SSH server is used. Under the right circumstances this interference could potentially enable a malicious actor to break sshd authentication and gain unauthorized access to the entire system remotely. The malicious mechanism consists of two compressed test files that contain the malicious binary code. These files are available in the git repository,