Lack of signature replay protection in TimelockTimePool.sol withdraw function

[c4-bot-4]

Lines of code

https://github.com/code-423n4/2024-03-taiko/blob/f58384f44dbf4c6535264a472322322705133b11/packages/protocol/contracts/team/TimelockTokenPool.sol#L168
https://github.com/code-423n4/2024-03-taiko/blob/f58384f44dbf4c6535264a472322322705133b11/packages/protocol/contracts/team/TimelockTokenPool.sol#L208

Vulnerability details

Lack of signature replay protection in TimelockTimePool.sol withdraw function

Line of code

1. https://github.com/code-423n4/2024-03-taiko/blob/f58384f44dbf4c6535264a472322322705133b11/packages/protocol/contracts/team/TimelockTokenPool.sol#L168
2. https://github.com/code-423n4/2024-03-taiko/blob/f58384f44dbf4c6535264a472322322705133b11/packages/protocol/contracts/team/TimelockTokenPool.sol#L208

Proof of concept

In TimelockTokenPool.sol,

Line of code

  /// @notice Withdraws all withdrawable tokens.
  /// @param _to The address where the granted and unlocked tokens shall be sent to.
  /// @param _sig Signature provided by the grant recipient.
  // @audit
  // replay protection is missing
  function withdraw(address _to, bytes memory _sig) external {
      if (_to == address(0)) revert INVALID_PARAM();
      bytes32 hash = keccak256(abi.encodePacked("Withdraw unlocked Taiko token to: ", _to));
      address recipient = ECDSA.recover(hash, _sig);
      _withdraw(recipient, _to);
  }

Impact

there is lack of validation for signature replay,

then once the recipient sign a signature, anyone can replay the signature to trigger withdraw repeatedly

Line of code

  function _withdraw(address _recipient, address _to) private {
        Recipient storage r = recipients[_recipient];

        (,,, uint128 amountToWithdraw, uint128 costToWithdraw) = getMyGrantSummary(_recipient);

        r.amountWithdrawn += amountToWithdraw;
        r.costPaid += costToWithdraw;

        totalAmountWithdrawn += amountToWithdraw;
        totalCostPaid += costToWithdraw;

        IERC20(taikoToken).transferFrom(sharedVault, _to, amountToWithdraw);
        IERC20(costToken).safeTransferFrom(_recipient, sharedVault, costToWithdraw);

And this will let the sharedVault recipient replay the amountToWithdraw several times,

and force the _recipient to pay the costToWithdraw several times to drain the fund

that remain static in the _recipient wallet

Recommendation

mark the hash as used and do not allow signature reuse.

Assessed type

Token-Transfer

[c4-pre-sort]

minhquanym marked the issue as duplicate of #60

[c4-judge]

0xean marked the issue as satisfactory