Cross-chain bridges, also known as Blockchain bridges, connect different blockchain networks and authorize assets to be transferred between them. To ensure the safety and security of these bridges, developers must address several fundamental security concerns.
One major cause for concern is the possibility of asset hacking or theft. As assets are transferred between blockchain networks, they may become vulnerable to malicious actors’ attacks. This can result in the loss of assets and harm the reputation of the blockchain network. To mitigate this risk, it is critical to implement strong security measures such as encryption and multi-signature transactions.
According to a report by chainalysis, over $2 billion was lost in cross-chain bridge hacks by the end of 2022, demonstrating the severity of bridge attacks in the industry. In August 2022, approximately $190 million was stolen from the Nomad bridge before whitehat hackers returned $9 million to users.
Another point of concern is the possibility of smart contract bugs. Blockchain bridges, for example, frequently rely on smart contracts to facilitate asset transfers between networks. However, a bug in the smart contract could have unintended consequences, such as asset loss. To mitigate this risk, smart contracts must be thoroughly tested and audited before deployment.
While blockchain bridges have the potential to significantly improve the interoperability of various blockchain networks, it is critical to be aware of and address fundamental security concerns in order to ensure the safe and secure operation of these bridges.
Cross-chain bridges are classified into two types: trusted bridges and trustless bridges.
Trusted bridges are cross-chain protocols that hold a user’s tokens while bridging. Custodial bridges are another term for these protocols. When a user bridges from one blockchain to another, the tokens are locked into the bridge and are the responsibility of the organization that built the bridge.
Because users must give up crypto custody to a centralized entity when using trusted bridges, hackers may find it easier to compromise the protocol. This is because it is a midway point of control that malicious actors can target. A prominent example of a trusted bridge is the Avalanche Bridge on the Avalanche (AVAX). The tokens locked into the protocol are controlled by the Ava Labs organization.
Trustless bridges are decentralized bridging protocols that manage locked tokens and complete cross-chain transfers using smart contracts rather than a centralized authority. As a result, trustless bridges give users more control over their tokens and eliminate the possibility of a single point of failure.
However, trustless bridges are imperfect, and if there are vulnerabilities in the smart contract code, a malicious actor can compromise the bridge.
Pendulum, a decentralized network of smart contracts that connects fiat railways to the environment of decentralized finance, is one example of a trustless bridging protocol (DeFi). By connecting compliant currency-pegged tokens from major blockchain networks into different ecosystems within the decentralized finance space, the bridge increases fiat liquidity in the DeFi industry.
Ways to Prevent Future Exploitation
By analyzing the exploited vulnerabilities and implementing measures to prevent similar attacks in the future, blockchain platforms can learn from cross-chain bridge hacks. One approach is to use trustless or minimal trust operations in the bridge architecture’s construction.
Trustless or minimal trust operations are designs that do not rely on a centralized authority or intermediary to facilitate asset transfers between chains. Instead, smart contracts and cryptographic techniques are used in these designs to ensure the security and integrity of the transferred assets.
KXCO Armature by KXCO is a well-known example. The KXCO Armature is a proprietary blockchain that was developed to handle complex financial transactions and uses a proof-of-Authority validation concept. The KXCO Armature was built with KYC, AML, and Banking regulations in mind with a focus on the speed of transactions. With KXCO’s technology, it can automatically make the sidechain when a new coin pair is added to the chain. Chains can then be separated, isolated, and enhanced for specific functions.
Another example is the atomic swap, which allows for the exchange of assets between different chains without the use of a centralized intermediary. A smart contract is used to hold the assets in escrow and release them to the correct party once the terms of the exchange are met.
To summarize, blockchain platforms can improve the security of their cross-chain bridges and make them less vulnerable to attacks by implementing trustless or minimal trust operations.