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Erroneous Writing To Memory Instead Of Storage

What it detects​

Developers sometimes use a memory pointer when they meant to update a storage variable. Changes to memory are discarded after the call finishes, leaving the persistent state untouched. This detector searches for such mistakes.

Typical symptoms​

  • State variables not updated after function execution
  • Temporary memory copies modified instead of storage

Solidity snippet (v0.8.25)​

pragma solidity ^0.8.25;

contract StorageBug {
    uint256 public count;

    function badUpdate() external {
        uint256 c = count; // loads to memory
        c += 1;           // writes to memory only
    }
}

Why it matters on EVM​

Writing to memory instead of storage can disable critical logic, as updates never persist. Attackers may exploit the inconsistency or rely on unchanged values.