IT review 2021: Log4j/Log4Shell

As part of our review, we would like to look back at various major developments in IT in 2021. This blog post is about the Log4j/Log4Shell security vulnerability. 

Log4j/Log4Shell stands for a security vulnerability in the Java library that was discovered at the end of 2021. This vulnerability has received particular attention due to various warnings from public authorities. For example, the German Federal Office for Information Security (BSI) classified Log4j as an "extremely critical threat situation". This classification corresponds to the highest of the four possible levels for cyber security warnings. In addition, this Java library is used in a particularly large number of applications and the vulnerability can be exploited relatively easily.

As with all IT vulnerabilities, fixing the problem involves quickly and thoroughly identifying the error and installing the appropriate updates (which are intended to close the gap). This process has taken a long time due to the increasing complexity of digital applications.

After a few days, the problem was solved in most cases, but the concern and risk remains that in the meantime hackers have installed another backdoor through which the system could later be attacked. In such a case, the attack could no longer be linked to the Log4j/Log4Shell issue.