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low Input Validation No SWC entry CWE-20

Short Address / Calldata Padding (legacy)

SAFE-0089 Input Validation Checked automatically by the scanner
1

What goes wrong

Legacy ERC-20 clients could send under-padded calldata; the EVM zero-pads it, shifting parameters (e.g. inflating an amount). Mostly mitigated by modern compilers/ABI decoding but relevant for hand-rolled calldata parsing.

2

How to fix it

the pattern that is safe
require(msg.data.length >= EXPECTED, "short calldata"); // when parsing manually
◆
Validate calldata length in low-level parsing.
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-0074Array Length Mismatch in Batch Operations medium · Input Validation SAFE-0072Missing Zero-Address Validation 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
← PreviousABI Encoding Collision / Selector Clash
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