December 13, 2021 By Sofia Wyciślik-Wilson
If you are running a version of Apache Log4j between 2.0-beta9 to 2.14.1 (inclusive) the Log4Shell vulnerability is something you need to be aware off. Tracked as CVE-2021-44228, this is a serious and easily exploited RCE flaw in the open-source Java-based logging utility.
An attacker can exploit the security flaw to execute a remote attack by simply using a particular string as the browser user agent. Although the Apache Software Foundation has released a patched version of Log4j 2.15.0, not everyone is able to update straight away, and this is something that attackers are taking advantage of. Thankfully, security firm Cybereason has released a "vaccine" called Logout4Shell that protects against Log4Shell.