Minor rash on my cat?

Question

My 10-year old gray cat has about 6 small bumps, that look like a scabbed pimple or chicken pox.  Doesn't look like ringworm, don't see any fleas.  They are on her back, side, and one on the outer upper thigh. She is not scratching.  I have 2 other cats in the house (her daughters); she never goes outside.  Every rash I see online does not match hers.  The "pimples" are spread out, not near each other.  First I thought they were scratches, but they don't really look like it.  They are pink in color.  The top is dry, but they don't seem to have any pus or blood.  I winder if it's a food allergy?