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medium Input Validation No SWC entry CWE-20

Array Length Mismatch in Batch Operations

SAFE-0074 Input Validation Checked automatically by the scanner
1

What goes wrong

Batch functions take parallel arrays (recipients[], amounts[]) without checking equal length, causing out-of-bounds reverts or, worse, silent misalignment of values.

2

How to fix it

the pattern that is safe
function airdrop(address[] calldata to, uint[] calldata amt) external {
    require(to.length == amt.length, "length");
    for (uint i; i<to.length; i++) token.safeTransfer(to[i], amt[i]);
}
◆
Always validate parallel array lengths.
3

Where this has happened

Largest recorded losses in the same failure class — related, not the same bug:

$586M · 2022 BNB Chain Token Hub Input validation · 2022 $326M · 2022 Wormhole Input validation · 2022 $197M · 2023 Euler Finance Input validation · 2023 $190M · 2022 Nomad Bridge Input validation · 2022
4

Related vulnerabilities in Input Validation

SAFE-0073Missing Input Validation / Parameter Bounds medium · Input Validation SAFE-0072Missing Zero-Address Validation low · Input Validation SAFE-0089Short Address / Calldata Padding (legacy) low · Input Validation SAFE-0140Missing Zero-Address Validation on Critical Setter low · Input Validation SAFE-0255Array Index Used Without Bounds Assumption low · Input Validation SAFE-0304Missing Zero-Value Validation on Value-Moving Function low · Input Validation
← PreviousMissing Input Validation / Parameter Bounds
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