Summary

In the discord Patrick said, The arbiter can be the 0 address I would add this to the NatSpec because from the documentation it is not clear.

Previous submission:
Missing zero address check for arbiter. This is a low risk vulnerability. As a rule, there should always be checks to make sure that initialized addresses are never a zero address.

Vulnerability Details

Escrow.sol. #32-51

Tools Used

Manual Review.
Slither reference: https://github.com/crytic/slither/wiki/Detector-Documentation#missing-zero-address-validation.
Similarly: https://github.com/code-423n4/2021-07-spartan-findings/issues/144

Recommendations

Check the arbiter address is not zero.