wp-admin/user-new.php in WordPress before 4.9.1 sets the newbloguser key to a string that can be directly derived from the user ID, which allows remote attackers to bypass intended access restrictions by entering this string.
{
"binaries": [
{
"binary_version": "4.4.2+dfsg-1ubuntu1",
"binary_name": "wordpress"
},
{
"binary_version": "4.4.2+dfsg-1ubuntu1",
"binary_name": "wordpress-l10n"
},
{
"binary_version": "4.4.2+dfsg-1ubuntu1",
"binary_name": "wordpress-theme-twentyfifteen"
},
{
"binary_version": "4.4.2+dfsg-1ubuntu1",
"binary_name": "wordpress-theme-twentyfourteen"
},
{
"binary_version": "4.4.2+dfsg-1ubuntu1",
"binary_name": "wordpress-theme-twentysixteen"
}
]
}