Hi Jacob, yes this is legal in Cook County.
Prohibited -
A semi-automatic rifle that has the capacity to accept a large capacity magazine
detachable or otherwise and one or more of the following:
a. Only a pistol grip without a stock attached;
b. Any feature capable of functioning as a protruding grip that can be held by the
non-trigger hand;
c. A folding, telescoping, or thumbhole stock;
d. A shroud attached to the barrel, or that partially or completely encircles the
barrel, allowing the bearer to hold the firearm with the non-trigger hand without
being burned, but excluding a slide that encloses the barrel; or
e. A muzzle brake or muzzle compensator
.
This gun has none of those features. A handguard is not considered a barrel shroud. This is good to go in Cook County.
budsgunshop.com/feeds/state_reg/illinois_restrictions.pdf ,
Stay safe & have a great day!

It seems like it is Okay But, Randy below makes a valid point on the BS wording put fourth by these anti-gun lawmakers!!

Hi Jacob and welcome. Yes Sir. Legal and good to go for purchase/ownership in Cook County IL. Cheers, stay safe and enjoy!

Please check with a local FFL to be sure as I can read it different ways depending on this statement
A semi-automatic rifle that CAN ( what does Can mean It can accept a larger capacity mag or does it mean that it comes with a mag over 10 rounds this affects weather its legal or not due to the shroud) accept a magazine with over ten (10) rounds (detachable or
otherwise) AND one or more of the following:
✘ A semi-automatic rifle that has a fixed magazine, that has the capacity to accept more than ten
rounds of ammunition.
✘ A semi-automatic rifle that can accept a magazine with over ten (10) rounds (detachable or
otherwise) AND one or more of the following:
● Only a pistol grip without a stock attached;
● Any feature capable of functioning as a protruding grip that can be held by the
non-trigger hand;
● A folding, telescoping, or thumbhole stock
● A shroud attached to the barrel, or that partially or completely encircles the barrel,
allowing the bearer to hold the firearm with the non-trigger hand without being burned,
but excluding a slide that encloses the barrel;
● A muzzle brake or muzzle compensator.