As part of Cybersecurity Awareness Month, we’re highlighting a variety of security risks that companies should be aware of. Today, we’ll be focusing on Dangling DNS, a hidden but critical vulnerability that can put your company’s digital assets at risk. Let’s explore what Dangling DNS is, why it’s dangerous, and how companies can manage DNS records more effectively to prevent attacks.
What is Dangling DNS?
A dangling DNS record occurs when a DNS entry (such as an A, AAAA, or CNAME record) points to a service or website that no longer exists. When an organization decommissions a service but leaves the DNS record active, attackers can hijack the unassigned domain or subdomain by pointing it to their own server, leading to potentially serious security incidents such as data interception or phishing attacks.
Why is This a Security Risk?
When DNS records are not cleaned up after services or websites are retired, it creates a window of opportunity for cybercriminals. By taking control of these dangling records, an attacker can:
- Redirect traffic intended for your domain to malicious websites
- Launch phishing attacks
- Intercept sensitive data
The risk grows exponentially in organizations where websites and services are managed by different teams, or where no centralized DNS management process exists. When no single person or team oversees the DNS records, it’s easy for an inactive website to go unnoticed, but its DNS record remains in place—making it vulnerable to exploitation.
How to Prevent Dangling DNS
The best way to prevent dangling DNS is to have a strict DNS management process in place. Ideally, this process ensures that any deactivated website or discontinued service is promptly followed by the removal of its associated DNS record. However, in many organizations, DNS records for inactive websites can slip through the cracks. This is especially true in companies with large numbers of websites, where periodic DNS audits are time-consuming and can be easily deprioritized.
For companies managing dozens (or even hundreds) of websites, manual DNS checks become labor-intensive, taking up valuable resources and increasing the likelihood of errors. This is where automation becomes key.
Linking DNS Management with Automation
To prevent dangling DNS effectively, your centralized website management system must be linked to a mechanism that periodically verifies whether all DNS records (A, AAAA, CNAME) are still pointing to active websites or services. Unfortunately, many companies still rely on Excel sheets or outdated databases that are not connected to active scanning tools, making it difficult to identify which DNS records are no longer needed.
This is where the Nixon platform steps in. Nixon provides an up-to-date overview of all your websites and their associated DNS records. Even better, it continuously monitors for any inactive websites or services. If a website is decommissioned or a campaign goes offline, Nixon ensures that the relevant DNS record is also removed—eliminating the risk of dangling DNS.
Why Automate DNS Checks?
For companies with a small number of websites, manually checking DNS records might seem manageable. But as soon as you’re dealing with dozens of websites, it becomes a costly and error-prone process. It’s easy to miss records or forget to remove them, especially when resources are stretched thin. With the Nixon platform, you can automate these essential checks, saving time and reducing the risk of human error.
Conclusion
While DNS management may seem like a simple task, it quickly becomes complex when you’re managing a large portfolio of websites. In today’s resource-constrained environment, it’s inefficient to burden your team with manual DNS checks. Instead, let Nixon automate this process, keeping track of your web portfolio and ensuring that outdated DNS records are flagged and removed.
The Nixon platform helps CISOs by providing a complete view of all your websites and automatically identifying DNS records that are no longer needed. This way, you can focus on more critical security tasks while Nixon handles the routine, yet important, job of maintaining your DNS records.
And while you’re here, try the Nixon Digital Tracker Checker: a free Chrome extension to check if your cookie banners and tracking practices are working right. While it doesn’t apply to dangling DNS, it’s a helpful tool to see if your consent settings are up to standard. You can install and try it, all within a minute.
If you’d like to learn more, schedule a meeting with one of our experts here.