diff --git a/requirements.txt b/requirements.txt
index 4b6c7c74e4..f7e4a85e2a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -14,7 +14,7 @@ sqlalchemy-migrate>=0.9.6 # Apache-2.0
 netaddr!=0.7.16,>=0.7.13 # BSD
 netifaces>=0.10.4 # MIT
 httplib2>=0.7.5 # MIT
-lxml>=2.3 # BSD
+lxml!=3.7.0,>=2.3 # BSD
 passlib>=1.7.0 # BSD
 python-heatclient>=1.6.1 # Apache-2.0
 python-novaclient!=2.33.0,>=2.29.0 # Apache-2.0
@@ -36,14 +36,14 @@ oslo.serialization>=1.10.0 # Apache-2.0
 oslo.service>=1.10.0 # Apache-2.0
 oslo.utils>=3.18.0 # Apache-2.0
 oslo.concurrency>=3.8.0 # Apache-2.0
-PyMySQL!=0.7.7,>=0.7.6 # MIT License
+PyMySQL>=0.7.6 # MIT License
 Babel>=2.3.4 # BSD
 six>=1.9.0 # MIT
 stevedore>=1.17.1 # Apache-2.0
 oslo.messaging>=5.14.0 # Apache-2.0
 osprofiler>=1.4.0 # Apache-2.0
 oslo.log>=3.11.0 # Apache-2.0
-oslo.db!=4.13.1,!=4.13.2,>=4.11.0 # Apache-2.0
+oslo.db>=4.13.3 # Apache-2.0
 enum34;python_version=='2.7' or python_version=='2.6' or python_version=='3.3' # BSD
 xmltodict>=0.10.1 # MIT
 pycrypto>=2.6 # Public Domain