# connscan\_external\_internal **Explanation** The connscan\_external\_internal NDM detects connection scanning attempts hitting the customer's network from the Internet. It does this by monitoring for a high rate of aborted successful TCP connections, which may indicate an attacker attempting to discover available services or potential vulnerabilities on the network edge. The NDM triggers when it detects a threshold of connections to different services within a certain time period. **What to Look For** Scanning activity on the Internet is quite commonplace. If there are unexpected services exposed to the Internet, check firewall or other blocking rules to prevent unwanted exposure. **Related MITRE ATT\&CK Categories** [Reconnaissance: Active Scanning, Technique T1595 - Enterprise](https://attack.mitre.org/techniques/T1595) --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.fusion.vectra.ai/detection-models/library/reconnaissance/connscan_external_internal.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.