> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/cortex-xsiam/detect-investigate-and-respond-to-threats/asset-management/asset-classes/external-surface-assets.md).

# External Surface assets

The **External Surface** inventory provides a searchable, filterable view of the internet-facing assets that Cortex XSIAM has discovered and attributed to your organization, including certificates, domains, services, and websites. Navigate to **Inventory** → **All Assets** → **External Surface** to access the **All External Surface Assets** view, or specific categories including **Services**, **Websites**, **Domains**, and **Certificates**.

{% hint style="info" %}

### Notice

Requires the Attack Surface Management (ASM) add-on.
{% endhint %}

The following sections provide information about each External Surface asset type. For information about external IP address ranges, see Network configuration.

**External asset categories**

There are four categories of external assets:

* **Services:** Any internet-facing device or software communicating on an application-level protocol over the public internet. The services table includes detailed fields such as Active classifications, Business units, Discovery type, Externally inferred CVEs, and an Externally inferred vulnerability score.
* **Websites:** Represents the content and the software stack that was used to generate a website.
* **Domains:** All root domains and subdomains that Cortex XSIAM has attributed to your organization. Subdomains are automatically grouped under a wildcard domain asset if they resolve to the same IP address, and are collapsed under a parent domain if more than 1,000 subdomains are observed.
* **Certificates:** Cortex XSIAM tracks "cryptographic health" checks, flagging issues such as self-signed or expired certificates, and weak signature algorithms.


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