  allocPacket(payloadLen) {
    let pktLen = 4 + 1 + payloadLen;
    let padLen = 8 - (pktLen & (8 - 1));
    if (padLen < 4)
      padLen += 8;
    pktLen += padLen;

    const packet = Buffer.allocUnsafe(pktLen);

    writeUInt32BE(packet, pktLen - 4, 0);
    packet[4] = padLen;

    randomFillSync(packet, 5 + payloadLen, padLen);

    return packet;
  }
The software constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.