Security Measures was originally canon, but was retconned out by events in Fury's Big Week, I believe. Neither are the Hulk or Fury tales collected there. I own that volume and had forgotten Security Measures was in it. That also originally shipped as a mini comic with some of the Iron Man DVD sets (I had a copy that way). Still, it isn't canon.
Contact Pilgrim on Twitter and ask him. I was satisfied with the answer given to Captain France but he now seems to be answering his Twitter account again so just ask him for clarification. I don't use Twitter and have no interest in it so can't contact him that way myself, and as I said, I was satisfied with the answer given back then about what was and wasn't canon.
Luckily the modern MCU canon stuff is pretty straightforward: usually a two issue Prelude and Infinite comic that are all eventually collected into an official MCU TPB release. Occasionally they do adaptations of the films, and those are included as well since they're canon (though admittedly almost entirely redundant with the films). I include the adaptations just for completion's sake (the same reason why I didn't remove IM-Security Measures or the Hulk/Fury comics lightly or without careful consideration and official word).
Also, while
this isn't official word, it's been repeatedly stated what is canon officially by Pilgrim. They never mention Security Measures, though.
It's just filler material to justify a TPB collection and price.
Right, as some (actually most) of the "padding" or "filler" material is just reprints of old 616 Marvel comics featuring that character. Has no bearing on MCU (outside of inspiration for the MCU itself) continuity.
The Prelude and Infinite tales are canon, and apparently there may be exceptions like the new Jessica Jones one shot prequel comic by Bendis that's canon with the show and the MCU as well.
But Security Measures isn't canon.