bool LookupMatchInTopDomains(base::StringPiece skeleton) {
  DCHECK_NE(skeleton.back(), '.');
  auto labels = base::SplitStringPiece(skeleton, ".", base::KEEP_WHITESPACE,
                                       base::SPLIT_WANT_ALL);

  if (labels.size() > kNumberOfLabelsToCheck) {
    labels.erase(labels.begin(),
                 labels.begin() + labels.size() - kNumberOfLabelsToCheck);
  }

  while (labels.size() > 1) {
    std::string partial_skeleton = base::JoinString(labels, ".");
    if (net::LookupStringInFixedSet(
            kDafsa, arraysize(kDafsa), partial_skeleton.data(),
            partial_skeleton.length()) != net::kDafsaNotFound)
      return true;
    labels.erase(labels.begin());
  }
  return false;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.