diff --git a/2.7/windows/1809/Dockerfile b/2.7/windows/1809/Dockerfile
index 57ef18c..ce0024b 100644
--- a/2.7/windows/1809/Dockerfile
+++ b/2.7/windows/1809/Dockerfile
@@ -1,4 +1,4 @@
-FROM mcr.microsoft.com/windows/servercore:1809
+FROM mcr.microsoft.com/windows/servercore:2009-KB4579311
 
 SHELL ["powershell", "-Command", "$ErrorActionPreference = 'Stop'; $ProgressPreference = 'SilentlyContinue';"]
 
diff --git a/2.7/windows/1809/Dockerfile.base b/2.7/windows/1809/Dockerfile.base
index 23c99ad..fbbe152 100644
--- a/2.7/windows/1809/Dockerfile.base
+++ b/2.7/windows/1809/Dockerfile.base
@@ -1 +1 @@
-FROM mcr.microsoft.com/windows/servercore:1809
+FROM mcr.microsoft.com/windows/servercore:2009-KB4579311