Submitted by dipp, also found by 0x1f8b, csanuragjain, and pedroais
In the withdrawForETH function in RubiconRouter.sol, the targetPool may be any contract that implements the IBathToken interface and returns wethAddress as its underlying token. The withdrawnWETH amount could be set to the RubiconRouter.sol contracts WETH balance so that the contracts entire WETH balance is withdrawn, as long as the tagetPool does not transfer any WETH to RubiconRouter.sol. The caller of the withdrawForETH function would then receive the withdraw amount.
Check the contracts WETH balance before the caller is supposed to send the WETH and after the WETH is sent to confirm the contract has received enough WETH from the caller.
bghughes (Rubicon) confirmed 
HickupHH3 (judge) commented:
