Demons can attack anyone

Ephesians 6:12 (KJV) ” For we wrestle not against flesh and blood, but against principalities, against powers, against rulers of the darkness of this world, against spiritual wickedness in high places”. 

This verse describes the spiritual battle that takes place in the life of believers. Paul tells us our battle is spiritual, not physical. Spiritual battles occur at all levels in this world and beyond. The believer must be prepared for all types of attacks by putting on God’s armor. All Christians are called on to use the tools God has given us for surviving the attacks of the devil. 

Weak as well as strong can come under attack from demons. 

Source: https://www.bibleref.com/Ephesians/6/Ephesians-6-12.html#verse