> For the complete documentation index, see [llms.txt](https://docs.fusion.vectra.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fusion.vectra.ai/detection-models/library/post-compromise/communication_to_bad_rep.md).

# communication\_to\_bad\_rep

**Explanation**

The communication\_to\_bad\_rep NDM is designed to detect successful outbound connections to a known bad IP. The NDM triggers when a connection is made to an IP address that is on a deny list or has been identified as a malicious IP.

**What to Look For**

The communication\_to\_bad\_rep NDM Event may indicate that a host on your network is compromised. IP Reputation, Reverse DNS, and Whois information for the remote IP address identified by the event may add valuable additional context for your investigation. Check your endpoint security solutions for signs of infected systems and take action to remediate any identified security threats.

**Related MITRE ATT\&CK Categories**

[Command and Control: Application Layer Protocol, Technique T1071 - Enterprise](https://attack.mitre.org/techniques/T1071)

[Command and Control: Non-Application Layer Protocol, Technique T1095 - Enterprise](https://attack.mitre.org/techniques/T1095)

[Command and Control: Non-Standard Port, Technique T1571 - Enterprise](https://attack.mitre.org/techniques/T1571)


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