A range of 7km....... Since Crazy mentioned that the Gulfs of Iran is so narrow, I'd bet that if you sent a couple of mini-FACs, it might be able to attack ships with this torpedo/missile. (That's a small craft, maybe Dvora-sized, with no radar. You shouldn't need it anyway.)
The video didn't show us an underwater launch, so It doesn't prove that they know how to use it underwater. (Especially when their subs are foreign! I wouldn't be surprised if Russia helped though.)
If it's unguided, how will it kill a ship though? CVNs are armored. I doubt you can punch a hole in it. And since it's unguided, how'll it know if it's under the target? (The video showed us a straight shot only. Can't be guided.) I think this is more like their navy's bayonet, effective(still questionable.) at close range, a piece of trash out.
As for nuclear capability, it by sense wouldn't need it, and couldn't have it. Iran has no nukes to test it on, and since its range is only 7km, you are better off just filling your boat with the bomb and blow up 7km out. Nuclear explosions do affect a whole area afterall, more than the coverage of this thing.
This thing is probably nothing.
Iran announced its second major new missile test within days, saying Sunday it has successfully fired a high-speed torpedo capable of destroying huge warships and submarines.
It's not like other torpedos are designed to kill fishes and bomb whales.
------
There's a video on the Shkval?