system
Provide references for <CVE-2018-4227>.
user
Where can I find more information about <CVE-2018-4227>?
assistant
References are available at: https://efail.de/#cve, http://www.securitytracker.com/id/1041027, http://www.securityfocus.com/bid/104897, https://support.apple.com/HT208848, https://support.apple.com/HT208849.