eSentire is The Authority in Managed Detection and Response Services, protecting the critical data and applications of 2000+ organizations in 80+ countries from known and unknown cyber threats. Founded in 2001, the company’s mission is to hunt, investigate and stop cyber threats before they become business disrupting events.
We provide sophisticated cybersecurity solutions for Managed Security Service Providers (MSSPs), Managed Service Providers (MSPs), and Value-Added Resellers (VARs). Find out why you should partner with eSentire, the Authority in Managed Detection and Response, today.
On December 9th, security researchers released details and Proof-of-Concept (PoC) exploit code for Remote Code Execution vulnerability impacting the Apache Log4j Java-based logging library. The vulnerability is now tracked as CVE-2021-44228 (CVSS: 10); exploitation will allow a remote and unauthenticated threat actor to take control of systems with vulnerable versions of Apache Log4j.
There are reports of ongoing exploitation of CVE-2021-44228 in the wild. eSentire has observed exploitation attempts as of December 10th, 2021. Organizations are strongly recommended to ensure security patches are deployed or alternative mitigations are enabled.
What we’re doing about it
eSentire has developed and deployed rules for MDR for Network & MDR for Log to identify exploitation activity
eSentire has deployed post-exploitation rules for MDR for Endpoint, and are actively working to create additional MDR for Endpoint detections
eSentire is conducting Global threat hunts for exploit patterns
eSentire Managed Vulnerability Service (MVS) has added the CVE-2021-44228 plugin
Known attacker infrastructure has been blocked via eSentire’s global deny list
This is an evolving situation and eSentire Threat Intelligence team will continuing to track this threat for additional details and detection opportunities
At the time of this reporting, eSentire has not identified an impact to our products. However, our teams are diligently reviewing systems and will be taking appropriate action as needed. A further communication from the CISO Office will be provided in the near future
What you should do about it
After performing a business impact review, update to the latest version of Log4j2
If patching is not currently possible, alternative workarounds are available in the previous link
Continue to monitor and review vendor releases and apply vendor patches to address products making use of Apache Log4j2 in order to mitigate products being targeted by CVE-2021-44228 exploits
MVS customers can contact your Customer Service Manager to request for an ad-hoc scan for CVE-2021-44228
Review the additional information section for Auditing Log4J usage
Additional information
CVE-2021-44228 is alternatively known as Log4Shell or LogJam and impacts applications using Log4j 2.0-beta9 up to 2.14.1. The underlying issue resides in the Java Naming and Directory Interface (JNDI), which allows Java applications to access APIs for directory services such as LDAP or DNS. Vulnerable versions of Log4J do not sanitize user-input allowing an attacker to load a remote Java class file.
eSentire has observed opportunistic exploitation of this vulnerability to deliver cryptocurrency miner payloads and is taking action to block both the exploit and payload sources.
Example Log4J exploit string observed in User-Agent field of HTTP exploit attempt:
This vulnerability is high severity and impacts versions of Apache Log4j Java-based logging library, which is widely used in a variety of products, including major vendors. Organizations will need to ensure impacted products are patched as updates become available from vendors.
Identifying use of Log4J in your environment will be important to limiting impact long term. Exploitation observed by eSentire is currently focused on deploying cryptominers via opportunistic attacks against internet-accessible services.
Cookies allow us to deliver the best possible experience for you on our website - by continuing to use our website or by closing this box, you are consenting to our use of cookies. Visit our Privacy Policy to learn more.
