This is a reach. Yes it's another windows zero-day, but very little of the software in use on windows machines even has the ability to download/make the user download and open a file in it's interface.
This is more geared towards the typical "Download this file now to make your penis 6 inches longer!" or "I tried sending you this email with how to make $50,000 more a year.DOCX" victim/crowd. As in the people who can't browse the web safely.
To identify this as "you use an SDR, and this can infect your computer because your SDR software uses fonts" is like saying "you drive a car, and yesterday a car was used in a crime 1,000 miles away and now you are a suspect."
Perfect tavern fodder.