The WPGraphQL 0.2.3 plugin for WordPress allows remote attackers to register a new user with admin privileges, whenever new user registrations are allowed. This is related to the registerUser mutation.
https://www.pentestpartners.com/security-blog/pwning-wordpress-graphql/
https://wpvulndb.com/vulnerabilities/9282
https://github.com/wp-graphql/wp-graphql/releases/tag/v0.3.0
https://github.com/pentestpartners/snippets/blob/master/wp-graphql0.2.3_exploit.py