Crypto bridges are a tool that enables the use of assets on one blockchain on another without transferring or exchanging them, solving the interoperability problem between blockchains. However, this solution has become a popular target for hackers, with an estimated $2bn stolen from bridging solutions in 2022 alone. Crypto bridges can be classified into various categories, including asset-specific, chain-specific, application-specific, and generalized bridges, each with a specific purpose. They can also be classified by their security mechanism, including trusted, trustless, insured, and bonded bridges. While many crypto bridges use varying degrees of trustlessness, they present risks associated with smart contract risk, technology risk, censorship risk, custodial risk, collateral as a target, under-collateralization, and loss of collateral value. The rise of crypto bridge exploits has led to the need for improvement in security and reliability, with developers needing to accept responsibility and prioritize the protocol’s security over all other aspects.