void Document::MaybeHandleHttpRefresh(const String& content,
                                      HttpRefreshType http_refresh_type) {
  if (is_view_source_ || !frame_)
    return;

  double delay;
  String refresh_url_string;
  if (!ParseHTTPRefresh(content,
                        http_refresh_type == kHttpRefreshFromMetaTag
                            ? IsHTMLSpace<UChar>
                            : nullptr,
                        delay, refresh_url_string))
    return;
  KURL refresh_url =
      refresh_url_string.IsEmpty() ? Url() : CompleteURL(refresh_url_string);

  if (refresh_url.ProtocolIsJavaScript()) {
    String message =
        "Refused to refresh " + url_.ElidedString() + " to a javascript: URL";
    AddConsoleMessage(ConsoleMessage::Create(
        kSecurityMessageSource, mojom::ConsoleMessageLevel::kError, message));
    return;
  }

  if (http_refresh_type == kHttpRefreshFromMetaTag &&
      IsSandboxed(kSandboxAutomaticFeatures)) {
    String message =
        "Refused to execute the redirect specified via '<meta "
        "http-equiv='refresh' content='...'>'. The document is sandboxed, and "
        "the 'allow-scripts' keyword is not set.";
    AddConsoleMessage(ConsoleMessage::Create(
        kSecurityMessageSource, mojom::ConsoleMessageLevel::kError, message));
    return;
  }
  if (http_refresh_type == kHttpRefreshFromHeader) {
    UseCounter::Count(this, WebFeature::kRefreshHeader);
  }
  frame_->GetNavigationScheduler().ScheduleRedirect(delay, refresh_url,
                                                    http_refresh_type);
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.