What is Log4j?

Log4j is an open source Java component, developed by the Apache Foundation and designed to store event traces.

Due to its ease of use and flexibility, log4j is used in many applications to record information in a log.

The wide adoption of Log4j has come to light after the discovery of a critical vulnerability in this component, which was called Log4Shell, due to the ease with which it allowed commands to be executed remotely on an affected system.