diff --git a/requirements.txt b/requirements.txt
index dc00740..27ba4f2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,13 +1,13 @@
 # The order of packages is significant, because pip processes them in the order
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
-pbr>=2.0.0 # Apache-2.0
+pbr!=2.1.0,>=2.0.0 # Apache-2.0
 PrettyTable<0.8,>=0.7.1 # BSD
 python-keystoneclient>=3.8.0 # Apache-2.0
 requests!=2.12.2,!=2.13.0,>=2.10.0 # Apache-2.0
 simplejson>=2.2.0 # MIT
-Babel>=2.3.4 # BSD
+Babel!=2.4.0,>=2.3.4 # BSD
 six>=1.9.0 # MIT
 oslo.utils>=3.20.0 # Apache-2.0
-oslo.log>=3.11.0 # Apache-2.0
+oslo.log>=3.22.0 # Apache-2.0
 oslo.i18n>=2.1.0 # Apache-2.0