To see mud in your dream could indicate body problems in which some internal cleansing is needed. Mud dreams are common when people have a stomach ache.
To dream that you are walking in mud, suggests that you are feeling weighed down by a situation, problem, or relationship.
To see others walking in mud in your dream, foretells that bad rumors about your friends will reach your ears.
It will be up to you whether to believe those rumors or not.
To dream that mud has gotten on your clothing means your reputation is being attacked by someone.