Oh Hell NO! Don't do that.
LOL...I once survived a few very cold nights (water bottles froze) in a summer sleeping bag. All the more hillarious since this happenend
in....Australia. The hot continent. Who knew it could get so cold there. Oh boy. My mistake.
It got me a first hand experience with hypothermia. I was able to extract myself from that situation and get to somewhere warm and safe. I learned a valuable lessen from it: Don't ever go winter camping in a summer sleeping bag. It was a mistake that I don't ever want to repeat again. Not ever. Thanks.
Don't use a summer sleeping bag in or near freezing conditions. Seems pretty obvious? And yet...I can recount so many other situations when people got themselves into this kind of trouble. Underestimating the weather conditions and, more often than not, overestimating the insulation capacity of their sleeping gear.
A summer sleeping bag can not be made into a winter sleeping bag. Don't even try.
If you expect night temperatures reaching near freezing than have at least a THREE-SEASON bag. Don't try it with a summer sleeping bag. I can't tell you how often I had people showing up with sleeping bags that were not warm enough.
If you are unsure, than better test your kit at home, in your garden. Or go car camping for one night. Worst case scenario, you have to get into your car and warm up there or drive home. Test your sleep system set-up BEFORE you go on a backcountry trip.