That's obviously a false positive. It should have been clear by the fact it was (as you say) "a new alert based on the recent updates being pushed by Norton", since the Couatl_Updater.exe hasn't been updated since a couple of months.
The tell-telling it's an antivirus bug, should be the name of the supposed threat, which contains the dreaded "Heur" word. When Heuristic is used, it means the antivirus doesn't really KNOW that is a threat, it's just guessing it, and it's basing its assumption on ANOTHER false assumption it made. In this case, the new "update", made the antivirus "smarter", trying to detect related threats.
In this case, since the Couatl_Updater *downloads* something from our site, and the site is the same as the site something THEY mistakenly think (because of THEIR bugged software) contains something dangerous, they also flag the downloader too.
There's really no reason to keep using that bugged antivirus, if you keep using it, it will end up stopping *everywhere*, because the basic concept over their heuristic works is entirely flawed. We keep reporting this to Symantect, and they ALWAYS reply this will be fixed in the "next upgrade", but instead, they keep getting more and more bugged with every update.
You don't have to wait for your subscription to end, just uninstall it and use the FREE, and ALWAYS updated Security Essentials from Microsoft. I cannot see why would want to *pay* to use something so bugged, when there are perfectly feasible free alternatives, that are not so bugged to begin with, and don't mistakenly identify any of our products as threats to begin with, so they don't require any special configuration.