CVE-2024-26149: Vyper's `_abi_decode` vulnerable to Memory Overflow

Summary

If an excessively large value is specified as the starting index for an array in _abi_decode, it can cause the read position to overflow. This results in the decoding of values outside the intended array bounds, potentially leading to bugs in contracts that use arrays within _abi_decode. The advisory has been assigned low severity, because it is only observable if there is a memory write between two invocations of abi_decode on the same input.