Submitted by Ruhum, also found by cccz, kenzo, xiaoming90, SmartSek, 0x1f8b, IllIllI, GimelSec, kenta, joestakey, berndartmueller, JMukesh, PP1004, Dravee, gzeon, shenwilly, sorrynotsorry, and z3s
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L356
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L374
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L434
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L451
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L491
https://github.com/code-423n4/2022-05-rubicon/blob/main/contracts/RubiconRouter.sol#L548
When transferring ETH, use call() instead of transfer().
The transfer() function only allows the recipient to use 2300 gas. If the recipient uses more than that, transfers will fail. In the future gas costs might change increasing the likelihood of that happening.
Keep in mind that call() introduces the risk of reentrancy. But, as long as the router follows the checks effects interactions pattern it should be fine. Its not supposed to hold any tokens anyway.
See the linked code snippets above.
Replace transfer() calls with call(). Keep in mind to check whether the call was successful by validating the return value:
bghughes (Rubicon) confirmed 
