Nasal Dryness or Irritation: This is often due to environmental factors such as dry air, overuse of nasal decongestants, or minor trauma. It's a common and benign condition that can cause discomfort and sores in the nasal passages.

Common Cold or Upper Respiratory Infection: Viral infections can lead to nasal congestion, runny nose, and subsequent irritation or sores in the nasal mucosa.
Allergic Rhinitis: Allergies can cause chronic nasal irritation, leading to sores or ulcers in the nasal passages due to persistent inflammation and irritation.
Nasal Septal Perforation: A hole in the thin wall of cartilage and bone (nasal septum) that separates the two sides of the nasal passages can cause crusting and sores.

Nasopharyngeal Carcinoma: Although rare, this type of cancer can present with nasal sores or ulcers among other symptoms like nasal obstruction or bleeding.
Wegener's Granulomatosis (Granulomatosis with Polyangiitis): An autoimmune disorder that can affect various parts of the body, including the nasal passages, causing sores, ulcers, and destruction of the nasal tissues.
Syphilis: In its secondary stage, syphilis can cause mucocutaneous lesions, including sores in the nasal area.
Leprosy: A chronic bacterial infection that can cause skin and mucous membrane lesions, including sores in the nasal area.

Sarcoidosis: An autoimmune disease that can cause granulomas in various parts of the body, including the nasal passages, leading to sores or ulcers.
Relapsing Polychondritis: A rare autoimmune disorder that can cause inflammation and destruction of cartilaginous structures, including those in the nose, potentially leading to sores.
Midline Destructive Lesions: Conditions such as midline granuloma or natural killer/T-cell lymphoma can cause destructive lesions in the nasal area, including sores.