Italian seems not to understand maroon as such.
The Oxford dictionary gives "marrone rossastro", i.e. reddish brown. The ending -astro (for -ish) seems to be usable with most other colours. A useful discovery.
Word Reference gives "granata", or "rosso granata". Since this is related to the colour of pomegranate (fruit) and garnet (stone), I don't think it is quite what I'd mean by maroon.
The Collins and Reverso dictionaries give "bordeaux", an invariant adjective directly from French.
The renowned paint maker Maimeri does not translate any of its many colours as maroon. It does have a Bordeaux, which is based on pigment PR12 in the international database, Permanent Bordeaux, which is classed as a bluish red. So not exactly maroon.
Take your pick. And why not add "rosso brunastro" (also from Word Reference) for completeness? :-)
It is a question of hypernyms and hyponyms, which vary by language. The English "blue" covers light blue and dark blue - many other languages, e.g. Italian and Russian, have separate names for these. We also say "pink" instead of "light red", so it seems inconsistent that there should be no separate name for light blue. But there you go. Language be illogical. Guy Deutscher's "Through the Language Glass" is a really good read on this and related topics.
As someone who is passionate about colour, I hate using 'marrone' to indicate plain brown also. Maroon is such a rich reddy-brown colour (which personally I am not a fan of). Brown in English covers so many shade from a light tan, to a rich chocolate, as well as all the tinted variations.
But then again, even in English I cannot use base colour names when a shade would do better. My car is a beautiful teal colour and I have interesting conversations with people. Some swear she's blue, and others green. I'd rather say teal.
However, even paint companies do not seem to know colours. Sometimes I will buy a shade of paint that I use a lot so that I do not have to mix it and it's completely different from a paint of the same name from a different manufacturer.