> 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/analytics-alerts/alerts-by-name/possible-new-dhcp-server.md).

# Possible new DHCP server

### Synopsis

| Field                | Value                           |
| -------------------- | ------------------------------- |
| Activation Period    | 14 Days                         |
| Training Period      | 30 Days                         |
| Test Period          | N/A (single event)              |
| Deduplication Period | 1 Day                           |
| Required Data        | XDR Agent                       |
| ATT\&CK Tactic       | Credential Access (TA0006)      |
| ATT\&CK Technique    | Adversary-in-the-Middle (T1557) |
| Severity             | Medium                          |

### Description

A DHCP response was sent from an unknown DHCP server. Attackers may send a DHCP response to a host in his LAN to inject a DNS server, route or WPAD server.

### Attacker's Goals

The attacker is attempting a man-in-the-middle NTLM relay attack to intercept authentication attempts and move laterally within an environment.

### Investigative actions

* Check if the source agent is a legitimate DHCP server.
* Check if the attacked host send DNS queries to an unusual IP.
* Check if the attacked host send WPAD HTTP/S requests to an unusual host.


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