isMalicious vs Shodan: Threat Reputation vs Attack Surface Discovery

Shodan and isMalicious both deal with IP intelligence, but they answer fundamentally different questions. Shodan asks: "What services and devices are exposed on this IP?" isMalicious asks: "Is this IP, domain, or URL malicious?"

Despite this difference, security teams often compare them because both appear when searching for IP lookup tools and threat intelligence platforms. Understanding what each tool actually does — and doesn't do — helps you pick the right one for your use case.

Quick Comparison

What is Shodan?

Shodan is an internet-wide scanner that crawls the entire IPv4 address space (and portions of IPv6) to identify what devices and services are accessible online. It indexes banners — the metadata that services broadcast when you connect — from HTTP servers, SSH daemons, databases, industrial control systems, IoT devices, and more.

Shodan excels at:

Attack surface mapping — discovering what your organization exposes to the internet
Service fingerprinting — identifying software versions, configurations, and potential vulnerabilities
IoT and ICS discovery — finding industrial control systems, cameras, and other connected devices
CVE correlation — matching detected services to known vulnerabilities
Historical data — tracking how an IP's services have changed over time

What Shodan doesn't do:

Shodan does not tell you if an IP is malicious. It tells you what's running on it.
No domain reputation checking
No URL scanning or phishing detection
No threat categorization (phishing, malware, C2, etc.)
Not designed for real-time threat blocking in production systems

What is isMalicious?

isMalicious is a threat reputation platform. When you query an IP, domain, or URL, it tells you whether that entity has been identified as malicious — and if so, what type of threat it represents (phishing, malware hosting, botnet C2, DDoS source, spam origin, etc.).

isMalicious excels at:

Real-time threat validation — instantly checking entities against 500M+ threat records
Production-grade blocking — sub-100ms responses designed for inline security decisions
Multi-entity coverage — IPs, domains, URLs, email addresses, and file hashes in one API
Streaming and monitoring — real-time threat feeds and watchlist alerting
Actionable intelligence — clear malicious/clean verdicts with threat categorization

What isMalicious doesn't do:

It does not scan for open ports or exposed services
No device or banner fingerprinting
Not designed for attack surface management
Does not identify what software is running on an IP

Different Tools, Different Questions

The core difference becomes clear when you look at what each tool returns for the same IP address:

Shodan for IP 203.0.113.50:

Open ports: 22 (SSH OpenSSH 8.9), 80 (HTTP nginx 1.22), 443 (HTTPS), 3306 (MySQL 8.0). Organization: Example Hosting. Country: Netherlands. Last seen: 2 hours ago.

This tells you the IP runs SSH, a web server, and an exposed MySQL database. Useful for attack surface assessment, but says nothing about whether the IP is sending malicious traffic.

isMalicious for IP 203.0.113.50:

Malicious: true. Threat categories: Malware distribution, Botnet C2. Risk score: 92/100. Sources: 14 blocklists. First seen: 2026-01-03. WHOIS: Registered to anonymous proxy service.

This tells you the IP is actively distributing malware and hosting botnet command-and-control infrastructure. Useful for deciding whether to block traffic from this IP.

Both results are valuable. Neither replaces the other.

Head-to-Head: Where They Overlap

IP Intelligence

Both platforms provide IP lookup, but the intelligence is fundamentally different:

Shodan tells you the IP's technical profile: open ports, running services, SSL certificates, geolocation, ASN, and organization.
isMalicious tells you the IP's threat profile: whether it's malicious, what type of threat, risk score, which blocklists flag it, and when it was first observed as malicious.

CVE and Vulnerability Data

Shodan identifies vulnerabilities by matching detected service versions to known CVEs. If it sees Apache/2.4.49, it can flag CVE-2021-41773 (path traversal).

isMalicious tracks vulnerability data differently — focusing on IPs and domains known to be actively exploiting vulnerabilities or hosting exploit kits.

Shodan's vulnerability detection is proactive (finding your own exposed vulnerabilities). isMalicious's is reactive (identifying threat actors exploiting vulnerabilities against you).

Monitoring

Both platforms offer monitoring capabilities:

Shodan Monitor tracks your organization's internet-facing assets and alerts on changes (new ports, new services, new vulnerabilities). Focus: your own infrastructure.
isMalicious Monitoring tracks entities on your watchlist and alerts when their threat status changes. Focus: external threats.

Pricing

isMalicious is significantly less expensive at every tier. But this comparison isn't quite apples-to-apples — Shodan's higher pricing reflects the cost of continuously scanning the entire internet, while isMalicious's pricing reflects aggregation and curation of existing threat intelligence.

If your primary need is threat reputation checking, isMalicious provides that capability at roughly 1/6th the cost of Shodan's entry plan.

When to Choose Shodan

Choose Shodan if:

Attack surface management is your priority. You need to know what your organization exposes to the internet — open ports, misconfigured services, and vulnerable software.
You're doing reconnaissance. Penetration testers and red teams use Shodan to map target infrastructure before engagements.
IoT/ICS security matters. Shodan is unmatched for discovering industrial control systems, cameras, and other connected devices exposed online.
You need service fingerprinting. Identifying specific software versions and configurations across internet-facing assets.
Historical internet data is valuable. Shodan's historical data shows how an IP's services have changed over time.

When to Choose isMalicious

Choose isMalicious if:

You need to block malicious traffic. Real-time reputation checking for IPs, domains, and URLs at sub-100ms speeds.
Threat categorization matters. Knowing whether an entity is associated with phishing, malware, C2, or spam drives different response actions.
You want affordable threat intelligence. Starting at $9/month for production API access.
Domain and URL coverage is needed. Shodan doesn't cover domain reputation or URL scanning.
Real-time streaming feeds are important. Push-based threat events with under 5-second latency.
You need production integration. SDKs, webhooks, and bulk APIs designed for application-level security.

The Best Approach: Use Both

Shodan and isMalicious are not competitors — they're complementary tools that address different layers of security:

Use Shodan to understand your attack surface. Discover exposed services, identify vulnerable software, and monitor changes to your internet-facing infrastructure.
Use isMalicious to block incoming threats. Check every IP, domain, and URL that touches your systems against 500M+ threat records in real-time.

Together, they provide both outward visibility (what you expose) and inward protection (what threatens you).

Example workflow:

Shodan Monitor alerts that a new service appeared on one of your IPs.
You investigate and find it's communicating with an external domain.
isMalicious confirms the domain is associated with C2 infrastructure.
You isolate the system and begin incident response.

Neither tool alone would have provided the full picture.

Conclusion

Shodan is a best-in-class tool for internet-wide scanning and attack surface discovery. isMalicious is purpose-built for threat reputation and real-time malicious entity detection. They answer different questions, serve different workflows, and complement each other in a mature security program.

If you've been using Shodan for threat reputation checks, you may find that isMalicious provides faster, more actionable results at a lower cost — while freeing up your Shodan quota for what it does best: mapping the attack surface.

Try isMalicious free. Check any IP or domain against 500M+ threat records — no credit card required.