Am i at risk of contracting a virus if i kiss someone on the forehead and they have a cold sore on their upper lip?

Low risk, but...: There is always a risk of catching or giving germs, viral or otherwise, when touching or being very near another person. That's the way life is. However, we humans much touch other humans. That's also the way life is. That said, cold sores are usually oral Herpes type 1, which is a virus that most people catch at some time. Many people catch it from their parents or siblings in childhood.