"remote" table function allowed arbitrary symbols in "user", "password" and "default_database" fields which led to Cross Protocol Request Forgery Attacks.
Credits: Andrey Krasichkov of Yandex Information Security Team
ClickHouse MySQL client had "LOAD DATA LOCAL INFILE" functionality enabled that allowed a malicious MySQL database read arbitrary files from the connected ClickHouse server.
Credits: Andrey Krasichkov and Evgeny Sidorov of Yandex Information Security Team