I think the development of a vaccine in a few months is unlikely. I think however the identification of somewhat effective antivirals in a few months is probable. There are already two antiviral candidates in trials, which are simpler to run than vaccine trials: remdesivir and lopinavir+ritonavir. Also, "transmitted immunity" is being (re)developed:

https://www.nbcnews.com/health/health-care/doctors-push-trea...

Antivirals won't stop the outbreak but they could save thousands of lives.