The TaxManagerETH contract presents significant centralization risks through its unrestricted tax management functions. The owner can set arbitrary tax percentages through setTax() without any maximum cap, potentially allowing a malicious or compromised owner to configure a 100% tax rate that would confiscate users' entire bridge amounts. Similarly, the stableMaxTaxAmount can be set to excessive values for stable coins, while the taxReceiver address can be changed to any address without zero-address validation. The contract also enables selective preferential treatment through the setTaxExempt() function, creating fairness concerns. Most concerning, for non-stable tokens, taxes are implemented by minting new tokens to the taxReceiver rather than transferring existing ones, potentially inflating token supplies. To mitigate these risks, the contract should implement: 1) a reasonable maximum tax percentage cap (e.g., 5% or 500 basis points), 2) validation checks for the taxReceiver address, 3) transparent logging of all tax exemptions through events, 4) a timelock mechanism for tax parameter changes, and 5) a governance or multi-signature requirement for changing critical tax parameters to prevent unilateral exploitation.

The Operator contract lacks an upper threshold when setting autoSendGasLimit, creating a centralization risk where the owner could set an excessively high value, causing most bridged funds to go to operators instead of users. Since the cost calculation is gasPrice * autoSendGasLimit, an unreasonably high limit could drain user funds under the guise of operator compensation. To mitigate this vulnerability, implement a reasonable maximum threshold with a constant like MAX_AUTO_SEND_GAS_LIMIT (e.g., 1,000,000) and add a require statement in the setAutoSendGasLimit function to enforce this boundary, ensuring that users receive the majority of their bridged funds regardless of owner actions.

The TokenRescuer contract, which is inherited by the BridgeETH contract, implements functions rescueTokens() and rescueEther() that allow the contract owner to withdraw any amount of any ERC20 token or ETH from the contract to any address. While these functions are common in bridge implementations to recover accidentally sent tokens or resolve emergency situations, they present a significant centralization risk since they have no limitations or safeguards. The TokenRescuer contract allows the owner to withdraw any tokens or ETH without restrictions, creating centralization risk. While common in bridges for emergency recovery, implementing timelocks, multi-signature requirements, and token allowlists would better protect user funds while maintaining recovery capabilities.

The TaxManagerOGPU contract presents significant centralization risks through its unrestricted tax management functions. The owner can set arbitrary tax percentages through setTax() without any maximum cap, potentially allowing a malicious or compromised owner to configure a 100% tax rate that would confiscate users' entire bridge amounts. Similarly, the stableMaxTaxAmount can be set to excessive values for stable coins, while the taxReceiver address can be changed to any address without zero-address validation. The contract also enables selective preferential treatment through the setTaxExempt() function, creating fairness concerns. Most concerning, for non-stable tokens, taxes are implemented by minting new tokens to the taxReceiver rather than transferring existing ones, potentially inflating token supplies. To mitigate these risks, the contract should implement: 1) a reasonable maximum tax percentage cap (e.g., 5% or 500 basis points), 2) validation checks for the taxReceiver address, 3) transparent logging of all tax exemptions through events, 4) a timelock mechanism for tax parameter changes, and 5) a governance or multi-signature requirement for changing critical tax parameters to prevent unilateral exploitation.

The BridgeETH contract's pause functionality introduces centralization risks by allowing a single owner to halt all bridge operations indefinitely. This creates vulnerability to regulatory pressure, potential fund locking during cross-chain transfers, and lacks emergency fund retrieval mechanisms. To mitigate these risks, implement: (1) multi-signature or DAO governance for pause decisions, (2) time-limited pauses that automatically expire, (3) tiered pausing to keep basic fund retrieval operational, (4) emergency withdrawal mechanisms for extended pauses, and (5) advance warning periods before non-emergency pauses. These changes would preserve emergency protection while reducing centralization and better safeguarding user funds.

The BridgeOGPU contract's pause functionality introduces centralization risks by allowing a single owner to halt all bridge operations indefinitely. This creates vulnerability to regulatory pressure, potential fund locking during cross-chain transfers, and lacks emergency fund retrieval mechanisms. To mitigate these risks, implement: (1) multi-signature or DAO governance for pause decisions, (2) time-limited pauses that automatically expire, (3) tiered pausing to keep basic fund retrieval operational, (4) emergency withdrawal mechanisms for extended pauses, and (5) advance warning periods before non-emergency pauses. These changes would preserve emergency protection while reducing centralization and better safeguarding user funds.