PowerDNS released two new versions which together add some features and address security issues.
Changelog: https://doc.powerdns.com/authoritative/changelog/4.1.html

This release and 4.1.9 together fix the following security advisories:

PowerDNS Security Advisory 2019-04 (CVE-2019-10162)
PowerDNS Security Advisory 2019-05 (CVE-2019-10163)

Signed-off-by: James Taylor <james@jtaylor.id.au>