Sui is pre-release software under rapid development. It has not been audited and is not yet ready for production use.
After we have completed internal and external audits of Sui, we will establish a responsible disclosure policy and a bug bounty program covering both protocol security and software security. In the meantime, please report security problems via an ordinary Github issue with the security tag.
See https://github.com/move-language/move/blob/main/SECURITY.md for reporting a security issue in the Move programming language.