This week, I read an article (in German) about a severe security bug in heating systems provided by Vaillant, one of the larger manufacturers in that space. The issue was found in so called “nano block heating systems” that are made for detached houses and duplex houses.

The entities have an IP-Interface that allows both the service technicians of the vendor and the owner of the heating system to remotely manage the device. However, a security bug allows pretty much anyone to easily access, in clear text, the passwords of the owner, the technician (expert), and even the developer. In other words: attackers can easily gain full access and control all settings. That allows increasing the temperature of the outgoing water in summer, which can damage the heating element. It allows stopping heating in winter, which could result in frost damages. There most likely are other types of damages an attacker can cause.

Even worse, these systems communicate with the DynDNS (Dynamic DNS) service of the vendor. That allows attackers to identify all systems in a simple way, just by “trial and error”.

Vaillant has announced that they will inform the customers, update the software – which requires, despite having an IP interface,  that a technician visits the customers - and provide VPN communication for technicians.

This issue is a perfect example of what is happening these days in smart metering and other areas of “smart homes”. Vendors start adding IP interfaces, but they fail in security. In the entire segment of home automation, which is based on standards such as EIB/KNX, understanding of security issues appears to be rather limited. Security is understood as “availability”, not as being secured against attackers. That is, by the way, true for other standards as well – most bus systems in manufacturing are not secure at all. EIB/KNX does not even have a security layer. These bus systems typically rely on simple broadcasting. Who has access to the bus, has access to everything. Once you connect the bus to the Internet, things become obviously highly insecure.

The obvious solution for that is protecting the IP interface. However, as long as that is not done perfectly well, the problem remains. The entire manufacturing industry, but also the automotive industry and others that rely on rather primitive bus systems, have to fundamentally rethink their security approaches. Not doing this is wantonly negligent.

Smart infrastructures require smart security. Not having well-thought-out and well-implemented security approaches in place but relying on stone-aged security approaches for (sometimes) stone-aged bus systems puts us all at risk. There is a good reason for the massive potential of Stuxnet: It arises by opening up unsecure environments – unsecure by design – to the Internet, without appropriately changing the security approaches.