Sources that always work (botvrij, disconnect, oisd, openphish, phishtank, quad9) drop their user-facing enable_* option; the rule's enabled/disabled state is now solely controlled by the SDK rule toggle. Sources that require credentials (criminalip, malwarebazaar, otx, pulsedive, safebrowsing, threatfox, urlhaus, virustotal) instead implement the new SourcePrecheck interface so the host UI can surface "not configured" before attempting a query.
ThreatFox queries the IOC database for domain indicators (C2 servers,
malware distribution, phishing); MalwareBazaar searches for malware
samples tagged with the domain. Both require a free abuse.ch Auth-Key.