Side Channel Attack: Everything You Need To Know

Every year, millions of people get victimized by data breaches. Criminals steal their data from the network environments of organizations, vendors, providers, institutions, and governments; with ever-increasing frequency, cybercriminals are making big moves in the cyber wars—and making billions of dollars. 

How cybercriminals launch their attacks differs based on their tech, skill, and target. Where one assailant may use sophisticated social engineering techniques to obtain credentials to an organization’s software, another malicious actor may exploit the same software’s vulnerabilities. They could target an organization’s vendor, breach multiple environments at once, or utilize malicious links to trick human employees into exposing their systems. Criminals have a vast arsenal of options—one of which is a side-channel attack. 

What is a Side-Channel Attack? 

The Internet of Things (IoT) is everywhere; it composes the technological world around us, from our phones and devices to cars, refrigerators, baby monitors, children’s toys, and everything else with an IP address. If it can connect to another electronic, it’s part of the IoT. Side-channel attacks in the IoT can be highly effective, utilizing the vast vulnerabilities of many low-quality devices.

Side-channel attacks differ from other penetration events in that they do not target a program, system, code, or platform directly. Instead, side-channel attacks collect data and influence a software’s execution of a command; these attacks exploit the indirect effects of the targeted hardware or system environment. Moreover, a side-channel attack definition might include that these attacks exfiltrate data—and they achieve this by measuring and analyzing the coincidental emissions caused by targeted hardware. 

How do Side-Channel Attacks Work? 

Also called “sidebar” or “implementation” attacks, side-channel attacks operate without interrupting the operations of a platform or hardware. Criminals launch these attacks while the target system is running. This means that for systems undergoing developments like cyber security updates, attackers can measure and analyze the changes happening within the environment without tipping off the security components of the software. 

Side-channel attackers position themselves “to the side” of an operating system rather than “on the path” of its target. Where an “on path” attacker positions themselves between protocol gates, a side-channel attacker hides just “off-path.” These “off-path” assailants can be difficult, if not impossible, to detect, especially when multiple people are utilizing the target hardware. 

The goal of a side-channel attack is not to breach or steal information from a target; instead, the goal is to gather valuable intelligence about the environment to assist in better exploiting the victim’s defenses. Depending on the assailant’s goals, the information gathered in a side-channel attack can help traditional attack vectors (i.e., brute force, SQL injections, etc.) to succeed. Thus, while side-channel attacks do not directly threaten an entity’s hardware environment, the information they collect can help to disrupt and damage an organization’s broader system. 

Side-Channel Attack Examples

Side-channel attack types vary vastly; depending on an organization’s hardware and operating processes, they could be more or less at risk for such attacks. Functionally, when some operating systems execute specific commands, there are physical effects produced by those executions. For example, some operations may create sounds or vibrations or leak electromagnetic radiation. Other times, operations can indicate specific executions by power consumption or processing time. The bottom line is that no matter what environment an organization uses to complete its obligations, they are at risk for a side-channel attack—whether or not organizations can recognize their potential weaknesses is another story. Criminals can use various options to launch a side-channel attack. Below are six of these methods.

Process Timing Attacks

When a user or program executes a command, the resulting time difference between request and fulfillment is called “processing time.” Side-channel attackers can use processing time to determine information about the operating system and its internal environment—especially if the organization has not added masking features to their operations. Attackers can compare the processing time of a known system to a potential victims’ system to make predictions, including precise cryptanalysis. Defenses for these attacks vary between systems; however, many organizations can mitigate side-channel attacks like this by implementing fixed processing times or randomized inputs that require further decryption. 

Acoustic Analysis Attacks 

These side-channel attacks have various versions and can be considered a broad category of systemic weakness. The problem with these attacks is their proximity necessity. Side-channel attackers must hear the system or its processes to derive information. For example, an audio recording of an employee inputting sensitive data using a keyboard may result in leaked passwords; simultaneously, the electronic components of a system could also betray valuable processing data. Such are the threats of speakerless operating systems, hard drive noise, and ultrasonic transmissions. Countermeasures against these side-channel vulnerabilities include filling the space with additional noise, launching acoustic shielding processes, or implementing modulus randomization. 

Electromagnetic Attacks

All electronic devices produce radio waves; by studying these waves, malicious attackers reconstruct the signals of a device down to a device’s operating screen. Although modern side-channel attackers primarily target cryptographic information within a system, some cyber criminals can still utilize electromagnetic data through walls without directly interacting with devices. Studies on electromagnetic vulnerabilities have suggested cybercriminals could even use USBs and mobile phones to reveal sensitive data. Countermeasures against these threats vary but can include increasing processing noise, implementing radio wave shields, and moving operations away from public access. In theory, the farther away from malicious attackers, the harder it is for them to decrypt the waves.

Optical Analysis Attacks 

While rarely used in enclosed organization locations, optical attacks can be costly for victims. Also called “shoulder surfing” events, optical assaults involve visual cues that expose information to the bad actor. For example, organizations that allow their employees to work from cafes may not realize how endangering the situation may be to their data. Anyone within a public setting could see sensitive data on their device and derive information from it. These threats surpass cafes, however—other visuals may expose a corporation’s data, from router LEDs to keyboard lights. Thankfully, mitigating these threats is simple—physically remove the lights from sight, and the threat dissolves.

Power Analysis Attacks 

If the malicious actor can access a system’s power consumption, they could monitor it to obtain unique information about that operator’s cryptography data. By analyzing the power consumption spikes of a system, a cybercriminal could deduce information about how the hardware operates and its keying material. There is no way to stop these breaches from being monitored, and because the technique is non-invasive, an organization wouldn’t necessarily know assailants monitored its power. For this reason, systems must take precautions to prevent this information from leaking. For example, running additional tasks may help hide the processing of sensitive data; however, if this occurs at a fixed rate, the assailants are likely to identify the pattern.

Memory Cache Attacks 

Although modernity has improved our devices’ performance, these improvements may be a weakness for some organizations. Memory caching and pre-fetched information are potential vulnerabilities. If an assailant accessed them, they could monitor the system’s behavior from within a secured environment—never giving a clue that they were watching. Additionally, the malicious actors could use this access to monitor other parts of the operation, resulting in them learning about the cryptographic algorithm of the hardware—despite being “present” in the software. For these reasons, organizations should never allow employees to use password-filling, bookmarking, or auto-access applications. 

Side-Channel Attacks and Countermeasures 

When considering side-channel attack cybersecurity, the most essential facets of defense begin with understanding the operating hardware and its interaction inside the IoT. For experts to mitigate the potential for these attacks, they start by analyzing the operating hardware, and through these analyzed channels, they can (hopefully) identify weak points within the process. Experts can create security and continuity plans that may help with mitigation upon identifying these vulnerabilities. 

Furthermore, the options available for mitigation depend upon the processes already built into the system. For example, systems with acoustic defenses can utilize increased noise within the hardware to distract and camouflage real functions. This increased operational noise also makes it difficult for side-channel attackers to locate helpful information. Meanwhile, companies concerned with electromagnetic or visual data breaches might consider moving their operating systems (and employees) into an isolated area. 

Other mitigation options include additional operation power costs, processing times, and electromagnetic leaks from specific hardware. In other words, increasing the outputted emissions—in any way—may be enough to deter side-channel threats. If not because of the increased challenge, then because of the increased time costs. However, every operating system is different. Consequently, what works for one organization may not work for another. Thus, companies need to rely upon experts in the area. 

Side-channel attacks are a massive threat to every industry and organization. They are virtually invisible and offer a way for cybercriminals to achieve their goals with increased vigor and scope. However, the right expert can create mitigating aspects within an environment that can render these attacks effectively useless (or at least time-consuming beyond benefit). Organizations in modernity must consider these aspects of cyber security—not only because it protects trade secrets, but because it also protects the public.