The official website. The vulnerability was introduced in 2.0-beta7 which was released in 2013. Source: over 1 year ago

What you need is log4j-core, what you downloaded is some kind of connector between log4j and JUL. Tbh I don't know what JUL is, but that's not important. You can get log4j-core on from the official website - https://logging.apache.org/log4j/2.x/ or in maven repo. In case you're not using maven, I highly, highly recommend you using it for managing your dependencies. Source: over 1 year ago

Log4J(https://logging.apache.org/log4j/2.x/) is a Java-based logging framework. It is a part of Apache Logging Services. It was also the most popular and widely used Java logging solution until the exposure of its Log4Shell vulnerability last year. - Source: dev.to / over 1 year ago

Almost nothing is more ubiquitous in applications than logging libraries. No matter which type of application - hastily thrown-together prototypes, decades-old enterprise monoliths, newly built event-driven serverless apps - there is always the need to log. Even in non-production-grade applications where standard observability patterns such as monitoring and alerting might not be applied - logging is usually... - Source: dev.to / over 2 years ago

Most applications currently use Log4J2 or SLF4J. Both provide a compatible System.Logger implementation. - Source: dev.to / over 2 years ago

If you want to use a service, check out trunc.org which works really well and makes the logs easy to read. Source: almost 2 years ago