Seedify finance Locked-Yield-Farming

In the contract `SMD_v5` the role `_owner` has authority over the functions shown in the diagram below. Any compromise to the `_owner` account may allow the hacker to take advantage of this authority and set rewards periods, extend the current period, pause/unpause functions, and withdraw excess tokens mistakenly sent to the contract. Notably, the hacker can prevent users from withdrawing staked tokens by updating `lockDuration` to a large value via `setNewPeriod()`. 

When transferring standard ERC20 deflationary tokens, the input amount may not be equal to the received amount due to the charged transaction fee. For example, if a user stakes 100 deflationary tokens (with a 10% transaction fee), only 90 tokens actually arrive in the contract. However, the user can still withdraw 100 tokens from the contract, which causes the contract to lose 10 tokens in such a transaction. If `tokenAddress` (the staking token) is deflationary, an attacker can repeatedly call `deposit()` and `withdraw()`/`emergencyWithdraw()` to empty the contract's funds and put other users' tokens at risk. Similarly, if the `rewardTokenAddress` (the rewards token) is deflationary, the actual balance is lower than anticipated, leaving the potential for insufficient funds when disbursing rewards. Reference: https://thoreum-finance.medium.com/what-exploit-happened-today-for-gocerberus-and-garuda-also-for-lokum-ybear-piggy-caramelswap-3943ee23a39f

The contract is serving as the underlying entity to interact with tokens `tokenAddress` and `rewardTokenAddress`. The scope of the audit treats third party entities as black boxes and assumes their functional correctness. However, in the real world, third parties can be compromised and this may lead to lost or stolen assets.