Here’s the original report: https://securelist.com/stripedfly-perennially-flying-under-the-radar/110903/

It doesn’t specifically attribute this to the NSA, and it’s very hard to definitively say who created what malware anyways.

That being said, if you read through the report, the details on this really scream “state actor” most probably. The level of modularity, the infrastructure of the C2 server, and the detailed & flexible spying capabilities all point to some government agency more than anything else.