Once a useful zero-day has been discovered by an adversary, it may make sense to give up using it so that one's own side's computers are not vulnerable. My gue

Once a useful zero-day has been discovered by an adversary, it may make sense to give up using it so that one's own side's computers are not vulnerable. My guess is that the NSA has excellent methods for detecting DNS exfiltration and the recent tools are at least a decade old technology. What's interesting is the disinformation value of intentionally releasing the tools, but to understand that we'd have to know who the intended adversary was.