Analyzing Threat Intelligence Feeds

When to Use

Use this skill when:

• Ingesting new commercial or OSINT threat feeds and assessing their signal-to-noise ratio
• Normalizing heterogeneous IOC formats (STIX 2.1, OpenIOC, YARA, Sigma) into a unified schema
• Evaluating feed freshness, fidelity, and relevance to the organization's threat profile
• Building automated enrichment pipelines that correlate IOCs against SIEM events

Do not use this skill for raw packet capture analysis or live incident triage without first establishing a CTI baseline.

Prerequisites

• Access to a Threat Intelligence Platform (TIP) such as ThreatConnect, MISP, or OpenCTI
• API keys for at least one commercial feed (Recorded Future, Mandiant Advantage, or VirusTotal Enterprise)
• TAXII 2.1 client library (taxii2-client Python package or equivalent)
• Role with read/write permissions to the TIP's indicator database

Workflow

Step 1: Enumerate and Prioritize Feed Sources

List all available feeds categorized by type (commercial, government, ISAC, OSINT):

• Commercial: Recorded Future, Mandiant Advantage, CrowdStrike Falcon Intelligence
• Government: CISA AIS (Automated Indicator Sharing), FBI InfraGard, MS-ISAC
• OSINT: AlienVault OTX, Abuse.ch, PhishTank, Emerging Threats

Score each feed on: update frequency, historical accuracy rate, coverage of your sector, and attribution depth. Use a weighted scoring matrix with criteria from NIST SP 800-150 (Guide to Cyber Threat Information Sharing).

Step 2: Ingest via TAXII 2.1 or API

For TAXII-enabled feeds:

taxii2-client discover https://feed.example.com/taxii/
taxii2-client get-collection --collection-id <id> --since 2024-01-01

For REST API feeds (e.g., Recorded Future):

• Query /v2/indicator/search with risk_score_min=65 to filter low-confidence IOCs
• Apply rate limiting and exponential backoff for API resilience

Step 3: Normalize to STIX 2.1