Subdomain Monitoring in Enterprise DNS Security
Preventing subdomain hijacking before it happens through active monitoring.
Subdomain hijacking occurs when cybercriminals exploit abandoned or improperly configured domain name system (DNS) records—or dangling DNS—to redirect traffic to malicious sites, often bypassing domain security protocols. This can enable other more egregious attacks like phishing and ransomware attacks, along with business email compromise (BEC), email spoofing, network vulnerabilities, or even data breaches—potentially causing significant reputation damage to the targeted brand—all without the criminal infiltrating an organization’s infrastructure or third-party service account.
The growing risks of unmanaged subdomains for enterprises
Enterprises with large domain portfolios to manage are a prime target for subdomain hijacking, phishing attacks, and brand impersonation. Bad actors often exploit misconfigured DNS records, in fact, one in five DNS records are left in a state that leaves them susceptible to subdomain hijacking. Subdomain takeovers are on the rise, and they leave brands, business operations, and their customers vulnerable.
Without enterprise-class subdomain monitoring, organizations risk unauthorized DNS record changes, that can redirect traffic, expose sensitive data, or distribute malware. A proactive subdomain monitoring solution enables IT security teams to detect vulnerabilities in real time, prevent subdomain takeovers, and maintain high levels of domain security.
CSC’s Subdomain Monitoring solution can mitigate the risks of subdomain hijacking, screening for and alerting you to changes to your zones, so you can take appropriate action to prevent a subdomain hijack.
Why enterprise subdomain security matters for regulatory compliance
For enterprises in regulated industries like finance and healthcare, ensuring DNS security is crucial for compliance with global cybersecurity standards.
Unsecured subdomains and abandoned DNS records create vulnerabilities that cybercriminals exploit for phishing attacks, data breaches, and brand impersonation—putting corporate and customer data at risk. Corporate DNS monitoring and enterprise subdomain security solutions help organizations prevent dangling DNS, enforce DNS protocol, and protect digital assets. Ensuring proper monitoring of DNS and subdomain records is essential for aligning with regulatory compliance frameworks.
By implementing enterprise-class subdomain monitoring, businesses can proactively check DNS configurations, maintain cyber hygiene, and align with IT security best practices, reducing risk while strengthening their cybersecurity and compliance position.
Why CSC’s Subdomain Monitoring solution?
CSC is the only enterprise-class security provider offering subdomain monitoring. It offers:
Better visibility
If you’ve experienced phishing attacks via an email service on a subdomain that bypassed your email fraud defenses, CSC’s Subdomain Monitoring solution provides you with visibility of threats to your brand via subdomains.
Improved security posture
Enterprises that undertake a lot of time-bound marketing campaigns that require subdomains will want to account for this as part of their security posture.
Scalability for growing enterprises
For multinational corporations with complex DNS environments, securely managing subdomains across multiple regions can be challenging. CSC’s enterprise-class Subdomain Monitoring solution is designed to scale with your organization, providing continuous DNS monitoring, automated alerts, and insights to safeguard your digital assets as your business expands.
CSC’s Subdomain Monitoring solution
It’s challenging for companies to account for all their digital assets and recognize which ones are critical, functional, or redundant. Our Subdomain Monitoring solution not only alerts you when changes to your DNS records or subdomain status are detected, but also provides you with the context needed to make informed decisions and take appropriate action. Our system continuously monitors DNS, detects security issues, and helps organizations resolve vulnerabilities before they can be exploited.
CSC’s Subdomain Monitoring solution:
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Monitors your CSC-managed DNS records daily
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Provides a system to clean up legacy records over time
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Sends alerts for new instances of zones changing from active to inactive so you can assess whether the zone needs to be purged, or a content delivery issue needs to be resolved, helping you resolve incidents quickly
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Integrates with DomainSecSM, our cyber intelligence tool
Frequently asked questions (FAQs)
Subdomain hijacking occurs when cybercriminals exploit an unused or misconfigured subdomain to redirect traffic, conduct phishing attacks, or distribute malware. For enterprises, this can result in data breaches, financial loss, and reputation damage, undermining customer trust and regulatory compliance.
Enterprise-class DNS monitoring continuously tracks DNS record changes, detects misconfigurations, and alerts IT security teams to vulnerabilities before they can be exploited. By ensuring only authorized subdomains remain active, organizations can significantly reduce the risk of subdomain hijacking and unauthorized access.
Industries that frequently create and manage subdomains—such as financial services, healthcare, eCommerce, SaaS, and government entities—are at higher risk. These organizations rely on subdomains for marketing campaigns, customer portals, and global operations, making proactive subdomain security essential.
Unlike traditional DNS monitoring, CSC’s Subdomain Monitoring delivers enterprise-class security, with daily DNS scans, real-time alerts, and seamless integration with existing cybersecurity and domain management tools. Our proactive approach helps businesses detect and mitigate threats before they impact operations.
To enhance subdomain security and DNS governance, enterprises should:
Conduct regular audits to identify and remove inactive subdomains
Enforce strict access controls on DNS configurations
Deploy automated subdomain monitoring solutions for real-time threat detection
