have (tiger) by the tail

Translations
иметь (тигра) за хвост
Managing such a large project is like having a tiger by the tail.
Управлять таким большим проектом — это как держать тигра за хвост.
Definitions
To be in a situation that is difficult to control or manage, often because it is risky or has gotten out of hand, similar to holding onto something powerful and dangerous like a tiger by its tail.
Words
tail

noun
хвост
have

verb
иметь