Internet of Things

to deliver updates securely. It is possible that a hacker may succeed in accessing the credentials

of AES with the help of SCA (side channel analysis). Afterwards, they misuse these keys and

take control of the street lights. This is not merely an example; there have been a number of

similar cases in the past.

In order to carry out such attack, the hacker must be within a specific device proximity

range so they can not only plan their attack but also collect private and sensitive data. In the

aftermath of the attack, there are no remnants. While we have so far described the vulnerability

of street lights, the SCA attacks have been used to launch cyber attacks in hospitals and banks as

well where their financial, reputational, and especially health-related damage can create severe

issues for the stakeholders.

Typically, physical vulnerabilities are split up into the following two vulnerabilities.

• Non-invasive attacks

In these attacks, the hacker has to be near enough so they can focus on the chip and modify

electrical characteristics. As a result, they are able to change the device behavior while at the

same time they copy sensitive information.

• Invasive attacks

In these attacks, it is necessary for the hackers to expose the surface of the chips; therefore it is

possible to manipulate the chip physically. Among the above-two attacks, a hacker can attack

with dierent methods of attack.

• Side channel analysis: It falls into the category of a non-invasive attack where a hacker

can determine the electromagnetic radiation or power signature from the Integrated

Circuit (IC) and target it to extract sensitive data like secret keys.

• Tamper attack: It is a type of invasive attack in which the hacker tries to ‘physically’ alter

the integrated chip with the aim of collecting sensitive or private data which exists in the

metal wires; to do this, they use microprobes. It is possible that they might even modify

the circuit’s behavior and overdrive the IC’s state.

• Perturbation attacks or fault injection attacks: These attacks happen when a hacker

exploits an IoT system’s flaw and aims to misuse it for compromising security. To exploit

such loopholes, there is a wide range of options. Interestingly, this attack can beboth

non-invasive and invasive.

Importance of Physical Security

Among all the above-mentioned four software vulnerabilities, hackers find it most convenient

to exploit the software vulnerabilities. Communication and lifecycle attacks are comparatively

harder to engineer, due to more stringent security measures.

Lastly, there is physical security which is the toughest for hackers to break into. A few years

ago, hackers were not too motivated to hack the physical security of IoT devices, perhaps due to

lower ROI (return on investment). With the passage of time, many things have changed which

has boosted the need for physical security. Some of these are follows.

• An introduction of more stringent security measures in other vulnerabilities.

• The rise of network connections which in turn coincides with the growth of assets,

creating more opportunity to launch a cyber attack on a larger scale, thereby offering a

high enough incentive.

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