Submitted by jnforja, also found by sl1, dimulski, wangxx2026 (1, 2), JohnSmith, 0xLogos, 14si2o_Flint, erosjohn, Aymen0909, Limbooo, Giorgio (1, 2), smaul, ZanyBonzy, 0xhacksmithh, Brenzee, btk, 0xDemon, lsaudit (1, 2), mrudenko, memforvik, Franklin, Shubham, and nmirchev8
https://github.com/code-423n4/2024-02-spectra/blob/main/src/tokens/PrincipalToken.sol#L483-L485 
https://github.com/code-423n4/2024-02-spectra/blob/main/src/tokens/PrincipalToken.sol#L460-L462 
https://github.com/code-423n4/2024-02-spectra/blob/main/src/tokens/PrincipalToken.sol#L278-L287 
https://github.com/code-423n4/2024-02-spectra/blob/main/src/tokens/PrincipalToken.sol#L229-L237
Protocols that try to integrate with Spectra, expecting PrincipalToken to be ERC-5095 compliant, will face an array of issues that may damage Spectras brand and limit Spectras growth in the market.
All official ERC-5095 requirements are on their official page. Non-compliant methods are listed below along with why they are not compliant and code POCs demonstrating the issues. To run the POCs, copy-paste them into PrincipalToken.t.sol:
 PrincipalToken::redeem and PrincipalToken::withdraw
As specified in ERC-5095, both withdraw and redeem must support a flow where msg.sender has approval over the owners tokens:
However, neither PrincipalToken::redeem nor PrincipalToken::withdraw support this flow type:
PrincipalToken::maxWithdraw
According to ERC-5095, maxWithdraw must not revert and must return 0 if withdrawal is disabled.
However, PrincipalToken::maxWithdraw reverts if PrincipalToken is paused:
PrincipalToken::maxRedeem
According to ERC-5095, maxRedeem must return 0 if redeem is disabled:
However, PrincipalToken::maxRedeem does not return 0 when PrincipalToken is paused:
Dravee (Judge) decreased severity to Medium
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