Yes. This is a hot pixel.

Basically, there is something wrong with one pixel. It can be more sensitive than others or captures some loose electrons in the sensor. In either case, the charge goes up faster than it should and while 1s is not enough, 20s is sufficient for it to accumulate a noticeable charge. In your particular case, the pixel happens to fall behind a red color-filter (that's a 1 in 4 chance), so it appears red but hot pixels (technically photosites) can cause the appearance of red, green or blue dots.

The camera can be calibrated to take into account such anomalies and usually is. It will then apply compensation for it. On some models it is possible to do it yourself using reference images but it is normally done by a service technician. If you do not have a local service center (for Canon in your case), then you have to call and get a reference number. Your send you camera there and get it back a few weeks later without the problem hopefully (and without a new problem as it sometimes happens unfortunately).