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low Token Standards No SWC entry CWE-459

Approval / Allowance Not Reset After Use

SAFE-0090 Token Standards Checked automatically by the scanner
1

What goes wrong

The contract grants an allowance to an external spender and never resets it, leaving a standing approval that a later-compromised spender can drain.

2

How to fix it

the pattern that is safe
token.safeIncreaseAllowance(router, amt);
// ... after use:
token.safeDecreaseAllowance(router, token.allowance(address(this), router));
◆
Scope and reset external allowances.
3

Related vulnerabilities in Token Standards

SAFE-0053Unsafe / Unprotected Minting critical · Token Standards SAFE-0051Missing SafeERC20 / Non-Standard Token Handling high · Token Standards SAFE-0052Fee-on-Transfer / Rebasing Token Accounting Mismatch high · Token Standards SAFE-0055Burn Authorization / Burn-From Missing Checks high · Token Standards SAFE-0107Fee-on-Transfer / Rebasing Token Mis-Accounting high · Token Standards SAFE-0208Non-Standard ERC20 Return Value Not Handled high · Token Standards SAFE-0050ERC-20 Approval Race Condition medium · Token Standards SAFE-0054ERC-721/1155 Missing Receiver Validation (Safe Transfer) medium · Token Standards
← PreviousShort Address / Calldata Padding (legacy)
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