Do you see hot pixels in your photos? These are supposed to be bright colored spots at fixed locations in the images. Similar to the defective pixels on LCD screens, they are typically caused by defects introduced during image sensor manufacturing process but some can develop over time.
You can certainly try to touch up the hot pixels in photo editing software like what you do with dust spots but it quickly becomes impractical for more than a few images. Fortunately, there is a completely free tool called Pixel Fixer for doing the task automatically for you.
It also has some other nice features, such as dark frame subtraction, extracting embedded JPEG images from RAW, and finding the total shutter counts.
READ: Pixel Fixer
Keywords: Hot Pixel, Pixel Fixer, Stuck Pixel