What Is URL Hijacking?

URL hijacking involves the unauthorized manipulation of web addresses to deceive end users and redirect them to fraudulent or malicious destinations. The goal of hijackers is to exploit user trust, harvest sensitive information, or inflict reputational damage on legitimate organizations.

What Is URL Hijacking?

URL hijacking is a malicious technique in which cybercriminals register, manipulate, or gain unauthorized control over domain names or URLs to mislead users. Attackers often rely on subtle alterations to legitimate URLs or on weaknesses in underlying network protocols. The result of successful URL hijacking is typically the redirection of unsuspecting visitors to fake websites, malware-infected pages, or other harmful digital destinations.

URL hijacking is sometimes conflated with typosquatting, but there are differences between the two, which are explained later.

URL Hijacking Methods

Cybercriminals use various methods to hijack URLs, each relying on different vulnerabilities or user behaviors.

Typosquatting

Typosquatting involves registering domain names that closely resemble legitimate sites. Attackers anticipate that users might make small typing errors when entering a URL, such as missing letters or swapping characters. By controlling these near-identical domains, hijackers intercept users who accidentally navigate to the wrong address. Typosquatted pages might display phishing forms, ads, or other misleading content that prompts users to disclose sensitive information.

Phishing-Based URL Hijacking

Phishing-based URL hijacking relies on social engineering rather than typographical errors. Attackers craft phishing emails or messages that embed malicious links disguised as legitimate URLs. The visible text may appear legitimate, but the underlying hyperlink diverts users to fraudulent sites. This method leverages trust in established brands to trick individuals into logging in, providing payment details, or downloading malware.

DNS Spoofing or DNS Poisoning

DNS spoofing (also known as DNS poisoning) compromises the domain name system resolution process, which translates domain names into IP addresses. Attackers tamper with DNS records on public or local DNS servers, causing a legitimate domain name to resolve to a malicious IP address. Users intending to visit a trusted site are sent to an attacker-controlled server instead. This method bypasses direct domain hijacking by targeting DNS infrastructure.

Session Hijacking

Session hijacking focuses on stealing or injecting session credentials during an active browsing session. While it does not typically involve changing the domain name itself, the user’s effective URL session might be hijacked by intercepting session tokens, cookies, or other authentication details.

Once attackers control the session, they impersonate the user or redirect the session to malicious resources. This method is technically distinct from domain hijacking but remains relevant because it relies on hijacking the flow of legitimate traffic.

Malware-Based Attacks

Malware-based approaches inject malicious code into a victim’s device, often through browser extensions or system-level modifications. Attackers alter the user’s hosts file or browser proxy settings to redirect traffic from a legitimate URL to a rogue site.

Such changes occur locally on the victim’s device and remain hidden from conventional domain security checks, making them challenging to detect without proper endpoint security measures.

What Is an Example of URL Hijacking?

A common example occurs when an attacker registers a domain with a minor alteration of a well-known financial institution’s official domain.

Let’s say the legitimate site is bankexample.com. An attacker registers bnakexample.com, anticipating that users might type the letters in the wrong order. Unsuspecting individuals who visit bnakexample.com are presented with a website that looks identical to the legitimate bank’s site. They proceed to enter login information, which the attacker captures.

This example illustrates a typical typosquatting-based approach to URL hijacking, though other variants rely on DNS spoofing or malicious redirects.

How Does URL Hijacking Affect Companies and Individuals?

The consequences of URL hijacking extend beyond simple annoyance and result in significant financial, legal, and reputational harm.

Financial Loss

Companies lose revenue when customers mistakenly visit fraudulent sites instead of legitimate pages, and individuals risk the theft of sensitive data, such as credit card numbers or passwords. There is also the potential for unauthorized transactions if financial credentials are stolen through phishing schemes.

Brand Reputation Damage

Organizations suffer reputational harm when customers unwittingly provide personal or financial details to scammers under the assumption they are interacting with the real brand. Publicized data breaches create mistrust, leading to reduced customer confidence. Even after the issue is resolved, lingering doubts about the brand’s security practices may remain.

Legal Implications

Businesses and website owners must invest significant resources in legal action to reclaim hijacked domains, address trademark violations, or sue offenders for brand infringement. Individuals may also become entangled in legal proceedings if they become victims of financial fraud, and their information is misused.

Privacy Compromise

Visitors who land on hijacked URLs often have their personal or confidential information harvested for illicit purposes. Attackers might use stolen data for identity theft, extortion, or unauthorized financial transactions. The exposure of private data strains relationships with customers and partners and requires remediation costs.

How to Check if a URL Is Malicious?

Here is how to avoid inadvertently exposing sensitive information or downloading harmful software:

• Inspect the domain carefully. Analyze the spelling, top-level domain (e.g., .com vs. .co), and any subtle character alterations. Attackers sometimes replace letters with visually similar symbols such as “l” (letter L) vs. “I” (capital I).
• Look at the URL protocol. Confirm that the site uses secure HTTPS encryption. Malicious pages often lack a proper SSL certificate, though attackers sometimes acquire fraudulent certificates, so this is not a foolproof indicator.
• Use URL scanning tools. Online services like VirusTotal or other reputable scanners aggregate malware detection results from multiple antivirus engines. Submitting a suspicious URL helps determine if others have flagged it as malicious.
• Check for browser warnings. Modern web browsers examine websites in real time and warn users when a site is suspected of phishing or distributing malware.
• Confirm certificates and Whois records. Investigate SSL certificates for mismatch errors and review the Whois registration details to see if the domain is registered to a legitimate organization.

How to Avoid URL Hijacking?

Here are some preventive measures to reduce the likelihood of domain-based attacks and ensure a secure browsing experience.

Register Common Misspellings

Companies purchase domain names that are close to their official domain. This practice, known as “defensive domain registration,” makes it harder for attackers to register near-identical domain names and exploit typos. Purchasing alternate top-level domains (.net, .org, .co, etc.) is also beneficial.

Use Secure Domain Management

Using strong registrar accounts with multi-factor authentication protects domain control from unauthorized access. Registrar lock features, also known as domain lock or transfer lock, prevent unintended domain transfer requests. Monitoring DNS records and renewing domain names before they expire prevents hijackers from opportunistically registering lapsed domains.

Educate Users and Employees

Employee security awareness training programs warn about phishing emails, suspicious links, and correct domain names. Providing thorough training ensures that staff remain vigilant while handling sensitive data or clicking on links, reducing the chance of a successful social engineering scam.

Use Threat Detection Tools

Organizations implement intrusion detection and prevention systems, firewall solutions, and DNS security solutions to identify anomalies such as unauthorized DNS changes or malware-based hijacks. Endpoint security software also helps detect malicious browser extensions or system-level modifications that redirect URLs.

What Is the Difference Between Typosquatting and URL Hijacking?

Typosquatting and URL hijacking are frequently used interchangeably, but there is a technical distinction between them. Typosquatting predominantly relies on mistakes made by end users when typing web addresses. Cybercriminals register domains with minor spelling alterations to capitalize on typographical errors. For example, an attacker might create googgle.com to trap individuals trying to reach google.com.

URL hijacking is a broader concept that covers various methods of redirecting legitimate traffic, including typosquatting, DNS spoofing, phishing-based tactics, session hijacking, and other deceptive approaches.

Typosquatting is one subcategory of URL hijacking, while URL hijacking as a whole describes any unauthorized manipulation of a web address or its resolution path. Both pose serious threats to cybersecurity, but typosquatting is narrower in scope, focusing specifically on domain name similarity and user typing errors.