The NSA has been gunning for two techniques, known as Simon and Speck, to be included in the International Organization of Standards (ISO). Following the accusations the agency, which says it "firmly believes" the techniques are secure, has agreed to drop all but the most powerful (and therefore less vulnerable) versions of Simon and Speck, but the issue has fostered significant mistrust and suspicion among countries which are supposed to be allies. Speaking to Reuters, Israeli ISO delegate Orr Dunkelman, a computer science professor at the University of Haifa, said, "I don't trust the designers. There are quite a lot of people in NSA who think their job is to subvert standards. My job is to secure standards."

Fears that the NSA were pursuing a "back door" into coded transmissions stem largely from NSA documents disclosed by Edward Snowden, showing that that agency had previously promoted technology it could penetrate. According to the reports, budget documents sought funding to "insert vulnerabilities into commercial encryption systems". The NSA, of course doesn't confirm the authenticity of these documents.