Brief Answer:
canker sores

Detailed Answer:
No.......usually not.

Canker sores,also called aphthous ulcers develop in the mouth,tongue,cheeks,lips,soft palate and throat area.
They do not occur in the roof of the mouth(i.e.hard palate).

If you have a sore on hard palate,that could either be a cold sore or a sore caused by hot foods-burn sore(also called Pizza palate) or candida.


Most of the sores of hard palate(roof of your mouth)are cold sores.The pic you have attached seems a cold sore.A common growth caused by the herpes simplex virus, they are usually found on the lips and on the hard palate.

Avoid stress,trauma,hot foods,irritation,acidic foods(i.e., tomatoes, citrus fruits etc),spicy and junk food,smoking and alcohol.

Topical corticosteroid preparations such as triamcinolone dental paste are helpful.

You can apply a pain-relieving gel to your sores during the recovery process.
Creams containing choline salicylate and local anesthetic lidocaine are available commercially which needs to be taken on fingers,massage it on the affected area,keep it for next 5 mins and rinse thereafter.Avoid eating or drinking anything for next half n hour.This can be repeated 3-4 times a day.

If your sores haven't healed after two weeks,consider consulting your doctor.
But don't worry at all.....malignancies of the hard palate are very rare.

Hope that I have answered your query and if you have any doubts,please let me know.
Regards

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