Thank you for sending this question to extension.  Yes this plant is a weed. This plant may be an annul, biennial or short lived perennial.  It was introduced from Europe.  It is an alternate host for ringspot virus, which infects sugar beets and spinach. There are several Silene  species plants that it could be but I am unable to identify the species from the picture.  The good news is they they are all weedy plants.

https://www.illinoiswildflowers.info/plant_insects/plants/silene_pratensis.html
https://michiganflora.net/species.aspx?id=782