Free threat intelligence feeds worth subscribing to

Compiled a list of free threat intelligence feeds and sources:

IP/Domain Reputation

• AbuseIPDB — Community-reported malicious IPs
• URLhaus (abuse.ch) — Malware URLs
• PhishTank — Community-verified phishing URLs
• AlienVault OTX — Open threat exchange

Vulnerability Intel

• CISA KEV (Known Exploited Vulnerabilities) — The "must patch" list
• NVD — National Vulnerability Database
• VulnCheck — Exploit intelligence

Malware/IOC

• MalwareBazaar — Malware sample sharing
• Feodo Tracker — Botnet C2 tracking
• ThreatFox — IOC sharing platform

RSS/Newsletters

• SANS ISC — Daily security diary
• The Hacker News — Breaking security news
• Krebs on Security — Investigative journalism
• TLDR Sec — Weekly security newsletter

All free. No excuses for not having threat intel.