Server Side Request Forgery in Apache Solr, versions 1.3 until 7.6 (inclusive). Since the "shards" parameter does not have a corresponding whitelist mechanism, a remote attacker with access to the server could make Solr perform an HTTP GET request to any reachable URL.
https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
https://www.oracle.com/security-alerts/cpuoct2020.html
https://security.netapp.com/advisory/ntap-20190327-0003/