Why DNS Dangling Can Turn Your Domain into a Ghost Office

An old DNS record – a configuration that directs Internet traffic to a specific domain name – can pose a significant modern risk that bad actors could exploit against your organization.

DNS dangling is like an office you no longer use, where your organization’s name and information remain associated with the location after you vacate the premises.

For example, if you leave the company’s sign on the door and fail to update the organization’s address in official directories, your brand remains linked to a vacated space. This is like a ‘ghost office’.

In the digital world, the phonebook listing and address can be seen as a dangling DNS record. DNS records are like instructions that direct Internet traffic to websites. If you stop using a service, such as a marketing promotional site, but your organization’s DNS record still points there, it leaves a visible trace of your presence. This trace becomes a 'ghost office' – a domain name that appears to belong to you but no longer serves your business. Anyone can potentially gain control and pretend to be your organization.

In this way, your domain name points to a DNS record, which then points back to the domain name, making it available to bad actors who can buy it and register it for their nefarious activities. Typically, the domain name you point to is no longer used by your organization, but the DNS record still exists, allowing bad actors to leverage it for their own benefit, such as in phishing campaigns or to damage your brand reputation.

Brand reputation and trust are central assets in modern marketing, and loss of these can affect revenue, communication, and business continuity. Accordingly, DNS dangling presents a substantial risk to your organization’s domain reputation and overall operations. In today’s interconnected organizations, teams must avoid operating in silos – marketing, IT, and brand management should collaborate. Alignment among deliverability (marketing), DNS hygiene (IT), and brand trust (organization) is essential to reduce risk. Leveraging DMARC reporting is fundamental for organizational intelligence, reporting, and actionable insights.

As a DMARC implementation consultant, I recommend using DMARC data for comprehensive risk management. DMARC data is valuable for threat intelligence and can identify:

• dangling risks when you suddenly notice email volume on domains that is unexpected
• suppliers you were not aware of that are sending emails (aka shadow IT)
• phishing campaigns that are spoofing your domain name

DMARC data is not just for identifying authentication gaps; it also supports all the use cases mentioned above, helping connect detection, threat intelligence, and response.

Modern risk stems from the organization's mistakes in its supplier onboarding & offboarding processes across domains. These mistakes create DNS Dangling risks that allow bad actors to do as they please. If you cannot explain or provide the purpose of every single DNS record within your organization, you are likely exposing yourself to risk through DNS Dangling. Therefore, it is time for you to review all your DNS records and remove any unwanted domains or records.

A useful article to begin or continue if you have not yet fully developed organizational processes for DMARC is this KB article: https://dmarcmanager.app/guide/guidelines-on-processes/

With that in mind, consider these essential steps to address and prevent this risk in your organization. 

​To address this, focus on three essential organizational capabilities:

1. Detection - finding the threat
2. Mitigation → fixing the threat
3. Prevention → stopping the threat from happening again

As I like acronyms, let’s refer to this as ‘DMP’

Detection (D)

Detection involves utilizing tools to identify risks and threats at the domain level before they escalate. Identifying an issue may still mean that prior failures, such as incorrectly offboarding suppliers, have allowed damage to occur. For instance, DMARC data can highlight unexpected email volumes from servers that your organization no longer uses. Once risks are identified, proceed to mitigation.

Mitigation (M)

Mitigation is the process of removing any identified dangling records to immediately eliminate the associated threat. If the DNS record cannot be deleted, take control of the domain name to prevent unauthorized use. If DMARC enforcement has not yet been applied to a domain, implement a p=reject policy to ensure only aligned and authenticated email is accepted, as a reject policy will cause all emails to fail unless they are aligned with and authenticated by SPF or DKIM. After mitigation, move to prevention.

Prevention (P)

Prevention ensures recurring risk is proactively managed. This requires ongoing monitoring and includes the following:

• (R) Real-time alerts → checking more than once a month or year
• (A) Automated scanning → using tools to help identify ‘dangling’ records
• (D) DNS first policy – always delete the DNS record of a supplier (external service or company) who will no longer be used as your first step
• (D) DMARC oversight → regularly reviewing DMARC reports to identify attacks
• (A) Automation → using software and tools to help automatically clean up when a supplier needs to be shut down; this is typically done in a project
• (C) Cross-team synchronization → teams like marketing & IT work together when shutting down a supplier

Use the acronym R-A-D-D-A-C to remember these key prevention elements and keep the sequence clear.

Security is a journey, not a destination. So take immediate action by reviewing your DNS records, aligning your teams, and implementing DMARC reporting to safeguard your organization against DNS Dangling risks today.

Mohammed Zaman is a consultant with DMARC Advisor. He thoroughly enjoys getting stuck into all things delivery & deliverability related and is currently focusing on DMARC, SPF & DKIM in relation to email authentication, domain abuse & security.