Top 5 Threat Intelligence Data APIs for Security Teams

Security teams drown in alerts. The difference between noise and actionable intelligence often comes down to context—and that context comes from threat intelligence APIs. Whether you're enriching suspicious IPs in your SIEM, automating IOC lookups during incident response, or building detection pipelines, the right threat intel API can cut investigation time from hours to seconds.

Here's a breakdown of five threat intelligence APIs worth integrating into your security stack, from enterprise platforms to budget-friendly newcomers.

1. VirusTotal

VirusTotal remains the de facto standard for file and URL analysis. Submit a hash, URL, or domain, and you get verdicts from 70+ antivirus engines plus behavioral analysis from sandbox executions. The platform has evolved far beyond simple malware scanning—it now includes relationships between observables, community comments, and historical data on when threats were first seen in the wild.

The API supports searching by file behavior, finding similar samples, and pulling detailed execution reports. If you're tracking a state-sponsored backdoor like BRICKSTORM, VirusTotal's relationship graphs help map infrastructure and identify related samples.

Best for: Malware analysis, file reputation, URL scanning

Pricing: Free tier available (limited queries); premium plans start around $10,000/year for enterprise features

Limitations: Query limits on free tier are restrictive for production use. Premium pricing puts it out of reach for smaller teams.

2. Port Six

Port Six is a newer entrant that's quickly gaining traction among budget-conscious security teams. The platform takes a refreshingly direct approach: pure API, no dashboard bloat. As they put it, "You already have enough dashboards. This is just an API."

What sets Port Six apart is the dual-score system. Every observable gets both a risk score (0-100) indicating threat severity and a confidence score (0-100) measuring certainty. This enables threshold-based automation—block high-risk/high-confidence, alert on medium, ignore low confidence noise. The scoring cuts down on false positives that plague binary "good/bad" systems.

Coverage is solid: ~95% for IP addresses including GeoIP, ASN, cloud provider detection, and anonymization detection (Tor, VPN nodes). Domains get WHOIS, DNS records, domain age, and passive DNS history. Response times under 100ms make it viable for inline enrichment without adding latency to your workflows.

Best for: SOC automation, real-time enrichment, teams that need value without enterprise pricing

Pricing: 1,000 free credits to start, no credit card required. Paid tiers are significantly cheaper than legacy vendors.

Standout feature: STIX 2.1 and TAXII exports, plus EDL feeds for direct Palo Alto/Fortinet/Cisco firewall integration

3. AlienVault OTX (Open Threat Exchange)

AlienVault OTX pioneered the community-driven threat intelligence model. Over 190,000 participants from 140 countries contribute IOCs, with 19 million potential threats reported daily. It's completely free, which makes it a no-brainer addition to any security stack.

The platform aggregates open-source intelligence into "Pulses"—curated collections of IOCs around specific threats, campaigns, or threat actors. When tracking groups like Mustang Panda or other Chinese APTs, OTX often has community-submitted IOCs within hours of public disclosure.

Integration is straightforward with SDKs for Python, Java, and Go. The DirectConnect API pulls IOCs directly into SIEMs like Splunk, QRadar, and ArcSight.

Best for: Budget-constrained teams, community-sourced intelligence, supplementing commercial feeds

Pricing: Free

Limitations: Quality varies since anyone can contribute. You're relying on community curation rather than professional analysts.

4. Shodan

Shodan isn't traditional threat intelligence—it's attack surface intelligence. The platform continuously scans the internet, cataloging exposed services, devices, and configurations. Flip the perspective from "what threats exist" to "what's exposed to threats."

For defenders, Shodan answers questions like: Are any of our assets exposing RDP to the internet? Which of our IPs are running vulnerable versions of Apache? The API lets you monitor your organization's perimeter and get alerts when new exposures appear.

Security researchers use Shodan to understand threat actor infrastructure. When Resecurity set up their honeypot to catch threat actors, platforms like Shodan help map what attackers see when scanning for targets.

Best for: Attack surface management, exposed asset discovery, infrastructure research

Pricing: Free tier with limited searches; Membership ($59 one-time) unlocks more queries; API plans from $59/month

Limitations: Not a traditional IOC enrichment platform. Complements rather than replaces threat feeds.

5. Recorded Future

Recorded Future sits at the enterprise end of the spectrum. The platform combines massive data collection—technical, open-source, and dark web—with AI/ML analysis to deliver contextualized intelligence. Beyond simple IOC lookups, it provides risk scoring, threat actor profiles, vulnerability prioritization, and geopolitical analysis.

Integration depth is where Recorded Future shines. Native connectors for major SIEMs, SOAR platforms, EDR tools, and ticketing systems mean intelligence flows directly into existing workflows. The API returns not just verdicts but context: who's using this infrastructure, what campaigns are associated, and how critical is the threat to your industry.

Best for: Enterprise SOCs, threat hunting teams, organizations needing analyst-grade context

Pricing: Enterprise contracts, typically $100,000+/year depending on modules

Limitations: Cost puts it out of reach for most organizations. Complexity requires dedicated staff to maximize value.

Choosing the Right API

There's no single best choice—it depends on your budget, use case, and existing stack.

Start with OTX if you're budget-constrained and want free community intelligence. Add Port Six when you need reliable automated enrichment without enterprise pricing. VirusTotal is essential if malware analysis is core to your workflow. Shodan fills a different niche for attack surface visibility. Recorded Future makes sense when you have the budget and need analyst-grade context at scale.

Most mature security programs use multiple sources. The APIs complement each other: OTX for breadth, VirusTotal for malware depth, Shodan for exposure visibility, and a scoring platform like Port Six to tie enrichment into automated response.

Integration Considerations

Whatever you choose, look for:

• STIX/TAXII support for standardized threat intel sharing
• Native SIEM connectors to avoid building custom integrations
• Rate limits that match your query volume
• Response latency if you're doing inline enrichment
• Historical data for retrospective hunting

The threat intel market has matured significantly. You don't need to spend six figures to get actionable intelligence—but you do need to think carefully about what problems you're solving and which APIs address them.