Facebook won’t let you change your security question, which can’t be updated. Giz alum Mat Honan’s account was hacked over the weekend by a hacker. Facebook’s security question is so simple that it’s impossible to change it. The only recourse is to manually change the security question to a new email address, or a new password. This is like replacing the locks on your house keys when the robber already has the keys, but with Facebook, you can’t replace your lock.”]
Source: https://gizmodo.com/the-giant-security-hole-that-facebook-doesnt-care-about-5986861