Shortly before the December holidays, a vulnerability in the ubiquitous Log4J library arrived like the Grinch, Scrooge, and Krampus rolled into one monstrous bundle of Christmas misery. Log4J maintainers went to work patching the exploit, and security teams scrambled to protect millions of exposed applications before they got owned. At Cribl, we put together multiple resources to help security teams detect and prevent the Log4J vulnerability using LogStream.
As CVE-2021-44228, a.k.a "Log4Shell" or Apache Log4j Remote Code Execution vulnerability continues to send shockwaves across the world of software, many security vendors and practitioners are rushing to provide recommendations on dealing with the crisis. If you need immediate help mitigating the impact of Log4shell, we're here for that. But the goal of this post is to look forward. This isn't the first and won't be the last high-impact vulnerability to be uncovered. So it's worth preparing your organization for the next one, so that you can respond faster, mitigate and remediate sooner - and have fewer weekends like the last one.
You have probably heard of Log4Shell, the security vulnerability that has ‘earned’ itself an NIST rank of 10: In this post I will show a really basic example of how this vulnerability actually works. I will walk you through some basic usage of the Log4J library and then show how some fairly basic inputs into this library can cause truly unexpected, and potentially disastrous, outcomes.
The Log4J library is one of the most widely-used logging libraries for Java code. On the 24th of November 2021, Alibaba’s Cloud Security Team found a vulnerability in the Log4J, also known as log4shell, framework that provides attackers with a simple way to run arbitrary code on any machine that uses a vulnerable version of the Log4J. This vulnerability was publicly disclosed on the 9th of December 2021.
If you have access to the internet, it’s likely that you have already heard of the critical vulnerability in the Log4j library. A zero-day vulnerability in the Java library Log4j, with the assigned CVE code of CVE-2021-44228, has been disclosed by Chen Zhaojun, a security researcher in the Alibaba Cloud Security team. It’s got people worried—and with good reason.