CVE-2021-22144
In Elasticsearch versions before 7.13.3 and 6.8.17 an uncontrolled recursion vulnerability that could lead to a denial of service attack was identified in the Elasticsearch Grok parser. A user with the ability to submit arbitrary queries to Elasticsearch could create a malicious Grok query that will crash the Elasticsearch node.
Date published : 2021-07-26
https://security.netapp.com/advisory/ntap-20210827-0006/
https://discuss.elastic.co/t/elasticsearch-7-13-3-and-6-8-17-security-update/278100