CVE-2021-29531: TensorFlow is an end-to-end open source platform for machine learning. An attacker can trigger a `CHECK` fail in PNG enc

TensorFlow has a vulnerability where an attacker can crash the system by sending an empty image tensor to the PNG encoding function. The code only checks if the total pixels overflow, but doesn't validate that the image actually contains data, so passing an empty matrix causes a null pointer (a reference to nothing in memory) that crashes the program in a denial of service attack (making the service unavailable).