Free Threat Intel feeds with YARA IOCs?

Can anyone give me a good list of, preferably free, up to date IOC feeds. Preferably YARA format so I don’t have to do a lot of data normalization.

I’m doing some research and am looking to set up an open source threat Intel feed that follows the MITR attack framework. I’m sure this has been done before, (in fact I’ve seen quite a few on GitHub) but I want to build one with my own connectors.

I’m finishing up …

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