diff --git a/requirements.txt b/requirements.txt
index cd31a7c..cf5f83c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ iso8601>=0.1.9
 netaddr!=0.7.16,>=0.7.12
 oslo.i18n>=1.5.0 # Apache-2.0
 oslo.serialization>=1.4.0 # Apache-2.0
-oslo.utils>=2.4.0 # Apache-2.0
+oslo.utils!=2.6.0,>=2.4.0 # Apache-2.0
 requests!=2.8.0,>=2.5.2
 python-keystoneclient!=1.8.0,>=1.6.0
 simplejson>=2.2.0