In the "Exploitation and Public Announcments" part of the linked article, it says that this vulnerability was discovered in the documents leaked/hacked from the

In the "Exploitation and Public Announcments" part of the linked article, it says that this vulnerability was discovered in the documents leaked/hacked from the Equation Group, which appears to be a group either within or extremely close to the NSA, although neither their actual name nor their existence has been acknowledged by the NSA. I don't see any reference to this exploit being used 14 years ago though, although the code being exploited is that old.