performing-ip-reputation-analysis-with-shodan

name	performing-ip-reputation-analysis-with-shodan
description	Analyze IP address reputation using the Shodan API to identify open ports, running services, known vulnerabilities, and hosting context for threat intelligence enrichment and incident triage.
domain	cybersecurity
subdomain	threat-intelligence
tags	["shodan","ip-reputation","enrichment","threat-intelligence","reconnaissance","vulnerability","api","internet-scanning"]
version	1.0
author	mahipal
license	Apache-2.0
nist_csf	["ID.RA-01","ID.RA-05","DE.CM-01","DE.AE-02"]

Performing IP Reputation Analysis with Shodan

Overview

Shodan is the world's first search engine for internet-connected devices, continuously scanning the IPv4 and IPv6 address space to catalog open ports, running services, SSL certificates, and known vulnerabilities. This skill covers using the Shodan API and InternetDB free API to enrich IP addresses from security alerts, assess threat levels based on exposed services and vulnerabilities, identify hosting infrastructure patterns, and integrate IP reputation data into SOC triage and threat intelligence workflows.

When to Use

• When conducting security assessments that involve performing ip reputation analysis with shodan
• When following incident response procedures for related security events
• When performing scheduled security testing or auditing activities
• When validating security controls through hands-on testing

Detection Gaps & Validation

• Banner staleness: Shodan results reflect the last scan, not now - a host may be remediated, reassigned, or the banner spoofed. Always check last_update/timestamp; a CVE list from a scan weeks old is a lead, not proof the service is still vulnerable. Re-run host(ip) for fresh data before a triage decision.
• Honeypots and decoys: mass open ports, conflicting service banners, and tags like honeypot/ics-honeypot mark a deception host - do not score it "critical" just for "20 open ports." Use the tags field and look for implausible service combinations.
• Shared/ephemeral attribution: cloud, CDN, VPN, and NAT IPs serve thousands of tenants, so reputation on a shared org (AWS, Cloudflare) says little about a specific actor. Pivot via ssl.cert.subject.CN, ssl.cert.serial, http.favicon.hash, and JARM facets rather than the IP alone, and avoid blocking shared infrastructure outright.
• Free InternetDB caveat: internetdb.shodan.io returns a reduced dataset (no banners, no timestamps) - fine for bulk triage but never the sole basis for a verdict.
• How to confirm: corroborate a "malicious" verdict with a second source - VirusTotal IP relations, GreyNoise to separate targeted activity from internet-wide background noise, and passive DNS - before escalating or blocking.

Prerequisites

• Python 3.9+ with shodan library (pip install shodan)