What is an On-Path Attack?

On-Path Attacks: Understanding, Detecting, and Preventing Data Interception

When it comes to attacking systems and intercepting sensitive data, on-path attacks – also known as man-in-the-middle or MITM attacks – are some of the most effective and devastating.

So much so, that research suggests cloud environments – in particular – are at grave risk from these attacks, accounting for around 35% of all cloud threats.

In this guide, we’ll take a look at what on-path attacks are, how they work, and why staying aware of them should be a crucial part of your risk monitoring strategy.

What Is an On-Path Attack?

An on-path attack occurs when a hacker intercepts two points through which data is being transmitted. This enables them to “listen in” or steal information while it’s in transit.

This type of cyberattack is particularly significant to businesses because it can be both discreet and destructive. Your reputation, private data, and even revenue are at stake if your network security allows eavesdroppers to attack on-path.

Eavesdropping is a term used to describe these attacks; however, attackers do more than just pick up sensitive data. They can alter the flow of information and insert harmful code, too – making on-path attacks one of the most dangerous types of cyber intrusion.

Typically, on-path attackers will target unsecure Wi-Fi and eavesdrop on financial programs and applications, often choosing businesses that handle lots of digital transactions.

“(A) Man in the middle attack allows the attacker to gain unauthorized entry into the connection between two devices and listen to the network traffic. This type of attack is very fatal because it is almost invisible to the victim device.”

K.P. Jain, M.V. Jain, and J.L. Borade

How Do On-Path Attacks Work?

Typically, a hacker will launch an on-path attack by exploiting a network vulnerability, such as poorly secured Wi-Fi, and place themselves between the data sender and the recipient. They can also exploit unsecure websites that don’t use HTTPS, because data is completely unencrypted.

By hijacking a data flow between, say, a user and a website, an on-path attacker acts like a go-between (hence man-in-the-middle). That means they can read, intercept, steal, and alter any information that comes their way, with neither victim being any the wiser.

That could mean someone who uses a financial app to send a transfer could find their money redirected to the attacker’s account. Or, an attacker could even steal and decrypt ecommerce transactions that would typically be bound for a receiving business.

On-path attackers are opportunists who silently exploit data privacy weaknesses – which, if you’re unprepared, could happen at any time.

Types of On-Path Attacks

On-path attacks take on various shapes and styles – which means, when working with our customers, we encourage them to use a variety of protective measures. We cover those ideas in more detail below.

Some of the most common types of on-path attacks include:

DNS Spoofing

DNS, or domain name systems, are easily manipulated by attackers who can redirect people to visit fake websites. By intercepting connections and spoofing the DNS, attackers can trick customers into giving up login and financial information via websites that look legitimate.

SSL Stripping

Your secure socket layer or SSL refers to your website’s data encryption, which should be the standard if your site runs on the HTTPS protocol. However, on-path attackers can “strip” the “S” and reduce the connection to purely HTTP, making connections unsecure and data visible to eavesdroppers.

ARP Spoofing

ARP, or address resolution protocol spoofing, is a technique that allows attackers to use an alternative IP address with the MAC address of a local area network they’re attacking. Essentially, this attack vector helps hackers to redirect traffic.

Wi-Fi Eavesdropping

This is a common attack method that allows hackers to sit in on public or unsecured Wi-Fi and therefore intercept any data that’s transmitted through it. They can create or access rogue access points to both listen in on and manipulate shared data.

Session Hijacking

It’s possible for on-path attackers to hijack user sessions post-login, or once details have been verified. This can be as simple as intercepting user cookies – which can then help them mimic the legitimate user, therefore gaining access to private information. Both HTTP and network sessions are at risk.

Email Hijacking

It’s even possible for on-path attackers to gain access to sensitive data through an email hijack. This method essentially sees an attacker installing themselves as a midpoint between users and an email server. Here, attackers can spoof email addresses to steal data without users realizing they’ve made a mistake.

Packet Sniffing

Packet sniffing is a technique where attackers use specific tools to intercept and analyze data packets that are transferred across networks. This is a highly passive but still detrimental attack, which some companies may not account for until the last possible moment.

Consequences and Risks of On-Path Attacks

On-path attacks can prove devastating for both businesses and private users. For example, those hackers who position themselves on-path can steal highly sensitive data that can be sold on, such as login information, and financial data.

On-path attacks can also expose highly private and sometimes top secret information, which can put companies at a disadvantage. Such data theft can also lead to fraud activity, which can harm individual and corporate finances.

As we’ve seen with a handful of customer cases over the years (who we’ve helped to protect for the better), on-path attacking can also give rise to malware distribution, which can cause further harm to finances and reputation.

Ultimately, a company that falls prey to on-path attacks could put its customers’ privacy and financial health at risk, as well as its own. That, in turn, leads to reduced customer trust and poor public image.

There’s also the risk of breaching data protection compliance, which could lead to fines – and large-scale attacks that require extensive remediation can also interrupt business operation flow.

How to Detect On-Path Attacks

We typically advise all our customers to focus on prevention, rather than cure, when it comes to on-path attacks. There are several typical tell-tale signs of this type of attack to help you plan ahead. Symptoms may include:

• ‍Network slowdown: If your network is running much slower than usual, it’s possible that attackers are using your resources.‍
• Drop to HTTP: Attackers may have stripped your SSL if your site’s URL suddenly drops the “S” from “HTTPS”.‍
• Unusual traffic spikes: If you notice increasing traffic to and from certain devices or locations you don’t recognize – or, if traffic is simply behaving erratically, you could be under attack.‍
• Certificate warnings: You may receive warnings that your SSL or TLS digital certificates are expired or “not trusted”.‍
• Website changes: Occasionally, slight changes to your website changes might indicate an attacker has made edits. This can even apply to slight changes in your website’s URLs, too.

Prevention and Mitigation Strategies for On-Path Attacks

We advise all our customers to regularly scan and test their security postures to prevent on-path attacks from ravaging their systems. Here are some of the most effective strategies that our clients have agreed upon over the years:

• ‍Keep certificates updated: Don’t neglect SSL and TLS. While these certificates can be stripped, simply encrypting your data in the first instance is a must.‍
• Monitor for anomalous network traffic: Continuous network monitoring and intrusion detection systems (IDS) help spot unusual patterns that might indicate an on-path attack in progress.‍
• Use secure MIME: Secure multipurpose internet mail extensions, or MIME protocols, can help crack down on email spoofing by requesting digital sign-offs from verified users.‍
• Avoid unsecured routers and Wi-Fi: Public and unsecured Wi-Fi are easy routes in for on-path attackers. Where possible, use a virtual private network (VPN) to shield your IP and ensure your connections are always secure.‍
• Run regular vulnerability scans: Vulnerability scanning and penetration testing, when run regularly, can help you spot hidden weaknesses in systems and infrastructures that attackers might typically exploit.‍
• Require multi-factor authentication (MFA): Applying MFA to your network security ensures that anyone who needs access to your systems must back up their login requests with additional verification measures, such as accessing an email or an SMS message.‍
• Use strong encryption for all data transfers: Beyond SSL/TLS, use additional encryption layers such as end-to-end encryption (E2EE) for sensitive communications.‍
• Keep software up to date: Outdated software is easy for attackers to exploit – always run updates when they’re due.

Preventing on-path attacks is possible, but with attack vectors growing ever more sophisticated, you need regular checks and measures to ensure your cybersecurity is up to scratch to defend your data.

VikingCloud can help – call our team today to find out more about preventive measures we recommend keeping your customers, data, and reputation safe.