Looks like NSA still hasn't forgiven Kaspersky for exposing STUXNET [1]. It seems that this latest attack on Kaspersky was expensive. Losing 4 zerodays must have been painful. It's also possible that Israel and Unit 8200 [2] was behind this but my money's on the NSA.
[1] https://eugene.kaspersky.com/2011/11/02/the-man-who-found-st...
[2] https://www.washingtonpost.com/world/national-security/israe...