MalShare
Malware Archive / file sourcing
Detonates files and URLs in instrumented VMs and returns behaviour, IOCs and ATT&CK.
Malwagon API is a free Anti-Malware API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Bearer-token REST API for submitting scans, polling status and reading reports, plus the MCP server and its tools. Rate limits and error codes included.
Details from malwagon.com.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Malware Archive / file sourcing
Provide malware datasets and threat intelligence feeds
IP/domain/URL reputation
The Malwagon API is provided by Malwagon (malwagon.com). Bearer-token REST API for submitting scans, polling status and reading reports, plus the MCP server and its tools. Rate limits and error codes included.
Yes. The Malwagon API is listed in the Anti-Malware category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Malwagon API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the Malwagon API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Malwagon API is served over HTTPS, so it's safe to use in production.