TXT Records

Required User Role: View only, Active User, Cloud Connector Manager, or Business Administrator.

On the TXT records page, you can view all text files in your inventory identified by Tenable Attack Surface Management.

What is a TXT Record?

A TXT record is a type of DNS resource record that allows domain administrators to store descriptive text in the Domain Name System. Unlike other records that facilitate network routing, TXT records are primarily used to provide machine-readable data for email security (SPF, DKIM, DMARC) and domain ownership validation.

If left unmanaged, TXT records can introduce significant vulnerabilities:

  • Subdomain Hijacking: Stale or "dangling" records can be exploited by attackers to hijack domain trust.

  • Email Spoofing: Overly permissive SPF (Sender Policy Framework) records may allow unauthorized servers to send malicious emails on your behalf.

  • Command & Control (C2): Attackers may hide malicious commands within TXT records to communicate with malware while bypassing traditional firewalls.

  • DDoS Amplification: Excessively large TXT records can be abused in DNS amplification attacks to overwhelm target networks.

Tenable Attack Surface Management simplifies your security by gathering all your TXT records into one searchable inventory. This makes it easy to perform regular audits to remove outdated records, enforce strict policies that prevent domain spoofing, and ensure your email security settings are precise and effective.

To view your text records:

  1. In Tenable Attack Surface Management, in the left navigation bar, click the button.

    The TXT records page appears. The TXT records table includes the following details:

    Column Description
    Host The hostname of the asset.
    Value The value of the text record.

  2. In the left navigation pane, use the Search box to search for a specific record or select the required record.

    Tenable Attack Surface Management displays the list of hostnames and the associated text records.

  3. (Optional) Use the filter to view specific text records.

    1. At the top of the table, click Add Filter.

      The Add Filter drop-down appears.

    2. Use the Search for Filters box or select the filter from the list: Hostname or Record Value.

      The list of operators appears.

    3. Select the operator. For example, contains.

    4. Type the value of the filter, if needed.

    5. Click Done.

    6. (Optional) To add another filter, click Add Filter.

      1. Repeat steps from 2 to 5.

        Tenable Attack Surface Management adds a new third filter to the list with the following options:

        • that match all filters —  Lists only the assets that match all the filters.

        • that match any filters — Lists assets that match any one of the filters.

      2. Select one of the options and click Done.

        Tenable Attack Surface Management shows the filtered results.