A flaw was discovered in Elasticsearch 7.17.0’s upgrade assistant, in which upgrading from version 6.x to 7.x would disable the in-built protections on the security index, allowing authenticated users with “*” index permissions access to this index.
The MITRE CVE dictionary describes this issue as:
A flaw was discovered in Elasticsearch 7.17.0’s upgrade assistant, in which upgrading from version 6.x to 7.x would disable the in-built protections on the security index, allowing authenticated users with “*” index permissions access to this index.
Vulmon