Zero-day-exploit in log4j2 which is part of elasticsearch

If you are using bash and the **/* does NOT work, then run shopt -s globstar before running the zip command.

shopt -s globstar
ls -lrt /usr/share/logstash/logstash-core/**/*/log4j-core-2.*
zip -d <output_of_above_command> org/apache/logging/log4j/core/lookup/JndiLookup.class
chown logstash:logstash <output_of_above_command>

Restart Logstash.