The high risk associated with newly discovered vulnerabilities in the highly popular Apache Log4j library – CVE-2021-44228 (also known as Log4Shell) and CVE-2021-45046 – has led to a security frenzy of unusual scale and urgency. Developers and security teams are pressed to investigate the impact of Log4j vulnerabilities on their software, revealing multiple technical challenges in the process.

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.

The discovery of the Log4Shell vulnerability in the ubiquitous Apache Log4j package is a singular event in terms of both its impact and severity. Over 1 million attack attempts exploiting the Log4Shell vulnerability were detected within days after it was exposed, and it may take years before we see its full impact.

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.

At many organizations, the surprise discovery that the widely used Apache log4j open source software has harbored a longtime critical vulnerability was as if Scrooge and the Grinch had teamed up for the biggest holiday heist of all. Incident response teams across the globe have scrambled to remediate thousands, if not millions of applications. “For cybercriminals this is Christmas come early,” explained Theresa Payton, former White House CIO and current CEO of Fortalice Solutions.

VMware has published a detailed analysis of the Log4Shell exploitation, explaining how VMware security products are helping in multiple ways to detect and contain the exploit. Source: Swiss Government Computer Emergency Response Team.

The internet has been ablaze since the announcement of Log4Shell, the nickname for CVE-2021-44228, an arbitrary remote code execution vulnerability in the Java logging utility Log4j. So far two additional vulnerabilities ( CVE 2021-45046, CVE-2021-45105) have now been identified. The code has been vulnerable since 2013 and millions of hosts and services are affected.

This post originally appeared on The New Stack and is re-published here with permission. In our technology-driven business climate, most companies have at least some, if not all, workloads on the cloud. And unlike on-premises networks, these cloud environments lack secure outer perimeters and specific off times. Cloud networks are always on and always available. While convenient, this also means hackers can access them at any time.

In our recent webinar, Log4j Log4Shell Vulnerability Explained: All You Need To Know, our Senior Director Security Research expert Shachar Menashe shared information on the security issue and how to detect and remediate it. We are happy to share additional information in the following Q&A, based on the questions raised during the webinar.

Just when the Microsoft Exchange exploit CVE-2021-26855 thought it would win the “Exploit of the year” award, it got unseated by the – still evolving – Log4J exploit just weeks before the end of the year! Had somebody asked Sysadmins in November what Log4J was then I suspect that the majority would have had no idea. It seems that the biggest challenge the Log4J exploit poses for Sysadmins is simply the fact that nobody knows all the places where Log4J is being used.