Submitted by xiaoming90, also found by joestakey, hansfriese, unforgiven, bin2chen, ladboy233, 0x52, aphak5010, hihen, 8olidity, cccz, and rvierdiiev
https://github.com/code-423n4/2022-11-redactedcartel/blob/03b71a8d395c02324cb9fdaf92401357da5b19d1/src/vaults/AutoPxGmx.sol#L73
https://github.com/code-423n4/2022-11-redactedcartel/blob/03b71a8d395c02324cb9fdaf92401357da5b19d1/src/vaults/AutoPxGmx.sol#L152
During initialization, the AutoPxGMX vault will grant max allowance to the platform (PirexGMX) to spend its GMX tokens in Line 97 of the constructor method below. This is required because the vault needs to deposit GMX tokens to the platform (PirexGMX) contract. During deposit, the platform (PirexGMX) contract will pull the GMX tokens within the vault and send them to GMX protocol for staking. Otherwise, the deposit feature within the vault will not work.
https://github.com/code-423n4/2022-11-redactedcartel/blob/03b71a8d395c02324cb9fdaf92401357da5b19d1/src/vaults/AutoPxGmx.sol#L73
However, when the owner calls the AutoPxGmx.setPlatform function to update the platform to a new address, it does not grant any allowance to the new platform address. As a result, the new platform (PirexGMX) will not be able to pull the GMX tokens from the vault. Thus, the deposit feature of the vault will break, and no one will be able to deposit.
https://github.com/code-423n4/2022-11-redactedcartel/blob/03b71a8d395c02324cb9fdaf92401357da5b19d1/src/vaults/AutoPxGmx.sol#L152
The deposit feature of the vault will break, and no one will be able to deposit.
Ensure that allowance is given to the new platform address so that it can pull the GMX tokens from the vault.
kphed (Redacted Cartel) confirmed 
Picodes (judge) decreased severity to Medium and commented:
