title: Vyper extract32 can ready dirty memory
description: Vyper is a pythonic Smart Contract Language for the ethereum virtual machine. When using the built-in `extract32(b, start)`, if the `start` index provided has for side effect to update `b`, the byte array to extract `32` bytes from, it could be that some dirty memory is read and returned by `extract32`. This vulnerability affects 0.3.10 and earlier versions.
problem types: CWE-125: Out-of-bounds Read
affected:
{
vendor: vyperlang
product: vyper
versions:
version: <= 0.3.10, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 3.7
baseSeverity: LOW
confidentialityImpact: LOW
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
version: 3.1
]