Are Open Ports Putting Your Network at Risk?

This guide explains why open ports remain a significant attack surface in 2025, outlines common threats (port scanning, brute-force, DDoS, botnets, lateral movement via SMB), lists high-risk ports (e.g., FTP 21, Telnet 23, SMB 445, SSH 22, RDP 3389, Elasticsearch 9200), and provides practical mitigations (default-deny, segmentation, identity-aware controls, replacing legacy protocols, continuous monitoring, internal encryption) while emphasizing third-party/supply-chain exposure and SecurityScorecard’s scanning and SCDR capabilities.