diff --git a/parts/agentparams.t b/parts/agentparams.t
index 8e6704a045..c8254cd2b4 100644
--- a/parts/agentparams.t
+++ b/parts/agentparams.t
@@ -60,7 +60,7 @@
       "type": "string"
     },
     "{{.Name}}osImageVersion": {
-      "defaultValue": "16.04.201803230",
+      "defaultValue": "16.04.201804050",
       "metadata": {
         "description": "OS image version."
       },
diff --git a/parts/masterparams.t b/parts/masterparams.t
index 6134e1bf1d..75817e4fb3 100644
--- a/parts/masterparams.t
+++ b/parts/masterparams.t
@@ -116,7 +116,7 @@
       "type": "string"
     },
     "osImageVersion": {
-      "defaultValue": "16.04.201803230",
+      "defaultValue": "16.04.201804050",
       "metadata": {
         "description": "OS image version."
       },
diff --git a/pkg/acsengine/defaults.go b/pkg/acsengine/defaults.go
index fb6460e0b6..c3ad894f5c 100644
--- a/pkg/acsengine/defaults.go
+++ b/pkg/acsengine/defaults.go
@@ -58,7 +58,7 @@ var (
 		ImageOffer:     "UbuntuServer",
 		ImageSku:       "16.04-LTS",
 		ImagePublisher: "Canonical",
-		ImageVersion:   "16.04.201803230",
+		ImageVersion:   "16.04.201804050",
 	}
 
 	//DefaultRHELOSImageConfig is the RHEL Linux distribution.