Add additional vulnerability for wordpress 4.7.1 that was initially kept
quiet by the wordpress team [1].

[1] https://make.wordpress.org/core/2017/02/01/disclosure-of-additional-security-fix-in-wordpress-4-7-2/

Security: https://vuxml.FreeBSD.org/freebsd/54e50cd9-c1a8-11e6-ae1b-002590263bf5.html