-Sphinx == 1.6.3
--e git+https://github.com/ceph/sphinx-ditaa.git@py3#egg=sphinx-ditaa
-breathe == 4.11.1
+Sphinx == 1.8.3
+git+https://github.com/ceph/sphinx-ditaa.git@py3#egg=sphinx-ditaa
+# newer versions of breathe will require Sphinx >= 2.0.0 and are Python3 only
+breathe==4.12.0
+# 4.2 is not yet release at the time of writing, to address CVE-2017-18342,
+# we have to use its beta release.
+pyyaml>=4.2b1