Extreme Threat
IP address 45.156.87.209 is a critical-risk address operated by Pfcloud UG under ASN AS51396 in the Netherlands, assessed at a 10/10 threat level with 94% confidence based on 161 total abuse reports and sustained activity detected between October 2025 and May 2026. The overwhelming majority of recent reports document SSH brute-force intrusion attempts and broader hacking activity originating from this IP.
Automated honeypot sensors recorded the majority of these 161 reports over approximately seven months, with 20 distinct honeypot sources flagging the address for malicious activity. The IP's activity frequency score of 8/10 indicates consistent, repeated offensive operations rather than isolated scanning. Suricata intrusion-detection systems specifically identified the signature pattern of SSH brute-force attempts alongside active SSH sessions established on expected ports, suggesting this host is actively engaged in credential-guessing campaigns against exposed SSH services. The network is registered to Pfcloud UG, a hosting provider in the Netherlands, and the volume of reports relative to the detection window points to systematic, automated attack infrastructure rather than opportunistic single-target probing.
SSH brute-force attacks represent one of the most common pathways for unauthorized server access in internet-facing environments. Attackers automate the submission of username and password combinations against exposed SSH daemons, exploiting weak or default credentials to gain shell access. Once compromised, servers become entry points for data exfiltration, lateral movement within networks, or recruitment into botnets. The detection of an established SSH session on this IP suggests active exploitation activity rather than mere scanning, elevating the risk profile considerably for any organization with SSH services reachable from the internet.
Site operators should treat 45.156.87.209 as a confirmed malicious source and block it at the network perimeter firewall or edge router level. Deploying automated blocking tools such as fail2ban can dynamically ban IPs after repeated failed authentication attempts. SSH services should be hardened through key-based authentication enforcement, non-default port assignment, and disabled root login. Continuous monitoring of authentication logs and implementation of network-level rate limiting on SSH ports will reduce exposure to similar brute-force campaigns from this and other threat actors.
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