Domain names play a critical role in how users access websites and services online. However, they also present significant cybersecurity risks if not properly secured and monitored. Attackers frequently target domain names as a way to intercept traffic, distribute malware, and carry out phishing attacks. In this article, we will examine the role of domain names in cybersecurity, the risks they present, and best practices organizations can follow to mitigate domain-related threats.
How Domain Names Work
A domain name like www.example.com is human-readable pointer to the unique IP address of a website or server on the internet. Domains operate through DNS, the Domain Name System, which maintains a directory matching domain names to IP addresses. When you type a domain name into your browser, it initiates a DNS lookup to find the corresponding IP address which it then uses to retrieve the website content from the hosting server.
Domains are registered and maintained through domain registrars and registries. Registrars handle the reservation of domain names and interface with registrants to handle registration and management. Registries operate the top-level domains like .com, .net, .org, and maintain the DNS records matching names to IPs. Domains ultimately point to the physical hosting server maintaining the website content.
This system creates a separation between the human-readable domain names users interact with, and the machine-oriented IP addresses required for locating content. Domains provide recognizable and memorable identifiers for websites and email, abstracting away the technical details. However, this abstraction also introduces vulnerabilities that attackers regularly exploit.
Cybersecurity Risks With Domain Names
While domains facilitate access and improve the user experience, they pose several risks from a cybersecurity perspective:
Domain hijacking is when attackers take over a domain without the authorization of the owner. This allows them to redirect traffic to malicious servers for phishing and malware delivery. There are several ways this can occur:
- Expired or lapsed registrations – If a registration expires, attackers can quickly purchase the domain.
- Compromised registrar accounts – By hacking the registrar account managing a domain, attackers can modify settings.
- DNS hacking – By compromising DNS records, attackers can modify where domains point.
- Domain theft – Domains may be stolen through compromised emails or insufficient identity validation.
Hijacked domains are dangerous since visitors are unaware the site is now malicious. Attacks leveraging recognized brand names have higher success.
Typosquatting refers to the intentional registration of domains containing misspellings or typographical errors of popular websites and brands. For example, amzon.com, googole.com, or applle.com. When users accidentally mistype a URL, they may land on a malicious typosquatted site.
Typosquatting domains are used to distribute malware and phishing content disguised as the legitimate brand they mimic. Even minor typos can be highly effective at capturing traffic from users making a mistake when entering a known brand name.
Domain Name Collisions
A domain name collision occurs when a registrant is able to register an active internal namespace used in another organization’s private network. For example, an internal server name like “reports” could be registered as a public domain. This can create confusion and possible security issues.
When external resolution of an internal namespace is possible, attackers may be able to exploit internal systems. It also creates the potential for data leakage if there are access controls differences between internal and external domains.
When domains expire and are not renewed, they become available for re-registration. Expired domains that were previously associated with popular services or brands can then be reregistered for malicious purposes.
Attackers may use previously trustworthy expired domains for phishing, typosquatting, scrape target lists, or other attacks that rely on reputation. Sites visitors recognize and trust are more effective phishing vectors.
Deceptive Domain Registration
Attackers sometimes register domains deceptively similar to popular brands and keywords by inserting hyphens, using alternate TLDs, or adding prefixes/suffixes. These domains are designed specifically to mimic legitimate sites for phishing and social engineering.
Examples include paypa1.com, applestore-check.net, or my-paypal.org. These domains take advantage of visual tricks and human error to manipulate users into thinking they are legitimate. Even vigilant users can be fooled by deceptive registrations designed to bypass filters.
Domain Security Best Practices
Organizations should follow these domain name security best practices to reduce risk:
Register Domain Variations
Defensive registration of alternate versions of core domains can reduce the risk of typosquatting or deceptive registration. Register common typos, hyphenated versions, and top TLDs like .com / .net / .org / .biz for critical domains.
Use Domain Registrar Locks
Enable registrar locks and multi-factor authentication for account access to prevent unauthorized transfers or changes. This protects against exploits targeting the registrar account and DNS hacking.
Monitor Expiration Dates
Actively track domain expiration dates so registrations do not inadvertently lapse. Set calendar reminders for renewals and auto-renew options if available. Letting domains expire, even briefly, can expose them to malicious re-registration.
Implement DNS Monitoring
Monitor DNS records for unauthorized changes that could indicate domain hijacking or DNS hacking. Watch for redirects, MX record changes, and newly inserted subdomains which are common malicious activities.
Enforce Domain Purchase Approval
Require security team approval for any new domain registrations to prevent unnecessary purchases and block typosquatting attempts. Review proposed names for security issues before purchase and registration.
Use Domain Authentication
Deploy DNSSEC, DANE, DMARC, and CAA records for your domains. These technologies add domain authentication and security policies to reduce spoofing, man-in-the-middle attacks, and fraudulent usage.
Include Domains in Monitoring
Add core domains to web application firewalls, endpoint detection, firewall allow-lists, threat intelligence feeds, and other monitoring and filtering defenses. Detect and block threats involving your domains.
Conduct Security Awareness Training
Train employees to identify risks like typosquatting and deceptive domains used in phishing emails or messages. Educate users on safely accessing and confirming legitimate URLs to avoid tricks and traps.
Domain names enable users to readily access websites and services through human-readable addresses. But poor domain hygiene and management can enable a variety of cyber attacks and exploitation by threat actors. Organizations should register domains defensively, secure account access, monitor DNS rigorously, and implement domain authentication technologies. Combining domain best practices with user education and adaptive security defenses can help mitigate the many risks introduced by domain names.