PAW Documentation

Crypto Bridges

Crypto Bridges

What is a Bridge?

A bridge is a pathway for assets to be sent from one blockchain to another.

How Do Bridges Work?

Bridges function through three main mechanisms:

       
  • Lock and Wrap: The original asset is locked on the source blockchain, and a wrapped version of the asset is created on the destination blockchain. When the asset needs to be moved back, the wrapped asset is burned, and the original asset is unlocked on the source chain.
  •    
  • Burn and Mint: The original token is burned on the source blockchain, and a replacement token is minted on the destination blockchain.
  •    
  • Lock and Unlock: Tokens are locked on the first blockchain and unlocked on the second blockchain.

Bridge Vulnerabilities

Bridges can have various vulnerabilities if not managed properly and are desirable targets for bad actors due to the value of the locked tokens. These vulnerabilities can stem from poor developer coding, inadequate operational security, bad faith actors in centralized networks, or the bridge code being open source.

Bridge Attacks

Common bridge attacks include:

       
  • Interception: Bad actors intercept communications between the blockchains being bridged and redirect transactions to their own wallets.
  •    
  • Denial of Service (DOS) Attacks: Bad actors overload a bridge with transaction requests to prevent legitimate bridge transactions from completing.
  •    
  • Parameter Manipulation: The parameters of the bridge are altered to create fake transactions.