Inyova’s short monthly newsletter about security recommendations, news, and interesting facts.
This is an internal newsletter sent to the Inyova team each month. We hope you enjoy it as much as we do!
Today’s topic: Cyber pandemic log4Shell
Sweet servers intro
Servers have a great memory and computing power, they provide data and services to other computers (aka clients) in their network. And of course, they reject offering their data and services to unauthorized entities.
All the activity that happens on servers is being tracked – logged. Thanks to that professionals can spot any interactions, behaviour, issues, cyber-security attacks, and more. For logging, they often use a well-known, widespread library – Log4j.
What happened?
On December 10, 2021, NVD published a 0-day vulnerability in java-based library Log4j. The vulnerability got the name Log4Shell.
News and blogs call the event a cyber-pandemic as Log4j is widely spread and the vulnerability is easy to exploit. The criticality was set to 10/10.
How Log4Shell works
Long story short, an attacker can pass a request to a server, the server logs the request, and the vulnerability allows it to run the malicious code.
Once that happens, the attacker opens a door to the server and can continue with any further attacks. All this is done remotely, without any authentication or authorization.
So to recap, anyone that is using this affected version of Log4j can have a server with all stored data under attack and stolen? — Yes. And the list of affected companies is pretty long.
What should I do?
As users, we cannot easily find out which concrete platform or app is using the affected version of Log4j. But, all players affected by Log4Shell immediately started releasing patches (fixes and workarounds).
Today, 1 month after the attack, we can assume that most of the big internet players have already released a stable and secure version of their product. Hence, the best shot is to update all your software.
What should companies do?
Inyova has verified that our setup is not affected by the Log4j vulnerability. The same approach should be taken by all other companies to minimise the impact of any future attacks.
That’s it! Keep your mechanics safe and thanks for reading.
Sources: https://nvd.nist.gov/vuln/detail/CVE-2021-44228
https://hackernoon.com/the-critical-log4j-java-vulnerability-how-to-detect-and-mitigate-it
https://engineerworkshop.com/blog/log4j-determine-server-affected-log4shell-vulnerability/
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