Comment by __strisk

There is a really good course on edX that goes over some key aspects of secure web applications. Just finished it myself. Learned a lot about preventing common oversights such as maintainable password hashing, XSS, CSP, Certificates, etc.

https://www.edx.org/course/web-security-fundamentals-kuleuve...

It pretty much goes over most of the OWASP top 10.