Its a passive voice participle clause and yes, its correct,
clauses are part of sentences. They vary and perplexing but if you want to learn them effectively, you need to be able to analyse all three kind of sentences and also clauses and phrases.
Participle clauses use a participle instead of a full verb. They can be defining and also non-defining.
Example: (Parking without permission) is an active voice participle clause.
Good luck X)