diff --git a/requirements.txt b/requirements.txt
index 5b300dfa..c245b2d2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,7 +6,7 @@ argparse
 iso8601>=0.1.9
 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
 PrettyTable<0.8,>=0.7
 python-keystoneclient!=1.8.0,>=1.6.0
 requests!=2.8.0,>=2.5.2