If you’re using any software running on Apache and Java, be aware of this critical zero-day vulnerability. Log4j is a ubiquitous logging tool included in almost every Java application, meaning this vulnerability affects literally millions of servers. The Log4J library vulnerability (CVE-2021-44228) allows an attacker to cause the target system to fetch and execute code from a remote location controlled by the attacker. The second stage, what the downloaded malicious code does next, is fully up to the attacker. This library is used by many software vendors and service providers globally as a standardized way of handling log messages within the software. This blog post is a step-by-step guide (recommendations) that you can follow.



