A good time to remember the official US Intelligence Community statement and policy/lie on 0days, as given post-heartbleed:
When Federal agencies discover a new vulnerability in commercial
and open source software – a so-called “Zero day” vulnerability
because the developers of the vulnerable software have had zero days
to fix it – it is in the national interest to responsibly
disclose the vulnerability rather than to hold it for an investigative
or intelligence purpose.
https://icontherecord.tumblr.com/post/82416436703/statement-...