Eavesdropping Attack

What Is an Eavesdropping Attack and How to Prevent One?

Reading Time: 5 minutes

In cyberspace, an eavesdropping attack refers to the interception of communication between two parties by a malicious third party. The hacker listens to communication traffic for the purpose of repeating it. Once this information is in the hands of a cracker, they can extract usernames, passwords, process procedures, etc.

Anyone can fall victim to an eavesdropping attack. In a business structure, it can affect internal teams, senior management members, or anyone who is directly responsible for communicating with vendors. Read on to find out how to spot these unwelcome intruders and keep your data safe from prying ears.

Eavesdropping Attacks – A Global Concern

Eavesdropping is not to be taken lightly. Unlike other forms of cyberattacks, eavesdroppers are hidden because they passively listen to your communications.

Last year, Russian hackers allegedly attacked Solarwinds and slipped a backdoor into an Orion software update. Instead of targeting the organization, the hackers targeted the suppliers in order to affect their customers. The hackers used an eavesdropping technique to slip the backdoor into the system. In the same year, an unknown spyware attacked users through Chrome web browser extensions. As a result, Google removed more than 70 of the malicious add-ons from its Chrome Web Store. Kr00k is another bug that takes advantage of a vulnerability in Wi-Fi chips which allows attackers to eavesdrop on Wi-Fi communications. In many cases, hackers used an extraction program that dynamically tried to extract the primary content from the traffic stream.

Hackers take the data collected through this activity and use it for their own malicious intentions. Some examples include:

  1. Hackers can make unauthorized purchases using bank account information. They can also use this information to transfer money into their account.
  2. They can commit identity theft to copy the personal address, medical records, identity proof, and other details. Anti-social elements can use this information to commit crimes for which the victim will be blamed.
  3. Stealing confidential information or classified data from individuals/businesses, and then blackmailing them in exchange for not leaking it in public. A lot of times, confidential information is stolen to be sold in the black market.
  4. Stealing passwords to access restricted areas of a digital network. This problem can cause severe damages that may include manipulation of different internal mechanisms.

Types of Eavesdropping Attacks

Modern network systems are wired and wireless. As a result, there are two common eavesdropping attacks — Passive Eavesdropping and Active Eavesdropping.

Passive Eavesdropping is more common in wireless networks. In this scenario, the monitoring tool detects the information by listening to the message in transmission. During an Active Eavesdropping incident, the monitoring tool actively captures the data transmitted over a wired or wireless network.

How Do Hackers Eavesdrop?

Malicious hackers always come up with new techniques. Eavesdropping in ethical hacking is a continually evolving process. When it comes to eavesdropping, new methods have been innovated to spy on digital conversations. Popular targets include Voice over Internet Protocol (VoIP) calls, which are made using IP-based communication. The conversations are recorded with the help of protocol analyzers and can be converted into audio files.

Data sniffing is another popular eavesdropping method. It works on local networks that use a HUB. This method is popular because all the communications within the local network are sent to all network ports. Eavesdropping becomes easier for the sniffer. They choose to accept all the incoming data despite not being the intended recipients. Wireless networking data can be manipulated similarly if it broadcasts unsecured information to all the network ports.

There are other eavesdropping attacks that are far more complicated, where hackers try to install malware or spyware under the pretext of social engineering. If they succeed, spying becomes easier.

Wireshark’s sniffing program caused a major problem for Android smartphone users back in 2011. During the attack, authentication tokens were sent over an unencrypted Wi-Fi network. Using these tokens, Wireshark could view, steal, and modify private data.

Awareness is the key to avoid eavesdropping. Every business has data and information to protect. Training employees with ethical hacking and social engineering practices will prove useful in preventing these issues.

Tips to Prevent Digital Eavesdropping

Eavesdropping in computer security is necessary because hackers are constantly looking for new methods to spy on digital conversations. Cybersecurity experts have to find fresh ways to identify eavesdropping attempts in order to safeguard data.

Listed below are some effective ways, popular among ethical hackers, to prevent eavesdropping.

Improving network security

A cybersecurity official must build a better and more effective network security infrastructure to avoid any kind of eavesdropping in ethical hacking. It will make the IT infrastructure capable of withstanding attacks from hackers. The internal and external systems are immune to any digital eavesdropping. A host of firewalls and antivirus software also assures a safe data exchange between two authorized points.


Data encryption is one of the key tools that cybersecurity experts must possess. Encryption is the process of data scrambling before sending it to the receiver. This way, the third party reading the data doesn’t understand the message. The actual receiver has an encryption key, which can be used to unscramble and retrieve the actual message.

Awareness and digital literacy

Apart from working on antivirus and firewalls, and building a stronger encryption system, every company should educate their employees about digital safety measures. Awareness about eavesdropping is not just limited to IT teams. Anyone who is using third-party platforms will find training on eavesdropping beneficial. Finance, Human Resources, marketing, social media, operations, etc., work in-sync with third-party apps for different purposes. These apps, if compromised, can cause financial loss and damage reputations in the market. Digital literacy also establishes a hierarchy with a point of contact that everyone can connect with during a suspicious activity.

Of the many courses and certification programs that experts recommend for these purposes, Certified Ethical Hacker (CEH v11) comes highly recommended, with many qualities ideal for training an internal IT team.

Learn All About Eavesdropping with Certified Ethical Hacker

Eavesdropping is a threat that is evolving as more and more systems are becoming dependent on the internet. Businesses across the globe have lost important confidential data in 2020 due to a third party listening in.

The demand for cybersecurity professionals with the skills to deal with eavesdropping, along with other network attacks, is at an all-time high. Developing these skill sets is a matter of picking the right course that touches upon common cybersecurity issues faced by a range of industries.

Since 2003, Certified Ethical Hacker (CEH v11) has been preferred by aspiring and entry-level cybersecurity professionals. The program uses real-world examples and guidance from industry experts to stay ahead of hackers. CEH adds credibility to your role as an ethical hacker by enhancing your skills to take on any challenge an eavesdropper throws your way.


What is used for the purpose of eavesdropping?
Eavesdropping involves the use of devices that pick up sound or video images and convert them to electrical impulses. Digital eavesdropping uses certain software or hardware designed to intercept data as it is transmitted over a network and decoded.
What is eavesdropping in cybersecurity?
Eavesdropping in cybersecurity occurs when a malicious actor tries to intercept a confidential communication. The hacker performs this activity in order to gain confidential information like passwords, bank details, social security numbers, etc.
How do hackers eavesdrop?
During an eavesdropping attack, hackers assess the system for weak connections between clients and servers. They prefer links that are not encrypted. To conduct an eavesdropping attack successfully, they use outdated devices or software. They often use social engineering to manipulate unsuspecting users into installing malware.
Is eavesdropping rude?
Eavesdropping is considered rude because it doesn’t involve the consent of the parties involved in the communication.
get certified from ec-council
Write for Us