This summary is devoted to the vulnerability that may affect Java Servers using log4j (CVE-2021-44228).
Please note, that Jelastic does not use log4j since using longback instead - an alternative project. Thus this CVE-2021-44228 doesn't affect the Jelastic platform core.
As an addition from a certified templates perspective, JavaEngine and WildFly templates contain log4j-api but not log4j-core. According to LOG4J2-3201 if you only depend on log4j-api, you are not affected by this vulnerability.