connscan_internal_internal

Explanation

The connscan_internal_internal NDM detects connection scanning attempts inside the customer's network. 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 network devices. The NDM triggers when it detects a threshold of connections to different services within a certain time period.

What to Look For

If the connscan_internal_internal NDM is triggered, network administrators should examine the source and destination IP addresses, as well as the ports and protocols involved in the connection attempts. They should also look for any patterns or trends over time, such as a sudden increase in connection attempts from a particular IP address. Endpoint agents should be checked for any sign of malicious activity or malware. Remediation should involve blocking the offending IP addresses and investigating any vulnerabilities or misconfigurations that may have allowed the scanning to occur.

Related MITRE ATT&CK Categories

Discovery: Network Service Discovery, Technique T1046 - Enterprise