Unknown flower

Unknown flower

Observation - Unknown flower - UK and Ireland. Description: Small plant growing on the land side of the dunes. Area closely cropped by rabbits. Tiny flowers 1-2mm across. They are white with five petals. Any ideas what they are?

Small plant growing on the land side of the dunes. Area closely cropped by rabbits. Tiny flowers 1-2mm across. They are white with five petals. Any ideas what they are?