diff --git a/.htaccess b/.htaccess
index afd4cab3..71c5a9f9 100644
--- a/.htaccess
+++ b/.htaccess
@@ -15,6 +15,8 @@ ErrorDocument 500 /assets/error-500.html
 
 <IfModule mod_alias.c>
 	RedirectMatch 403 /silverstripe-cache(/|$)
+	RedirectMatch 403 /vendor(/|$)
+	RedirectMatch 403 /composer\.(json|lock)
 </IfModule>
 
 <IfModule mod_rewrite.c>
diff --git a/composer.json b/composer.json
index 467ca6a1..400e90d1 100644
--- a/composer.json
+++ b/composer.json
@@ -14,4 +14,4 @@
 		"phpunit/phpunit": "3.7.*"
 	},
 	"minimum-stability": "dev"
-}
+}
\ No newline at end of file
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 2bb3c876..1232b66d 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -25,7 +25,7 @@
 	<listeners>
 		<listener class="SS_TestListener" file="framework/dev/TestListener.php" />
 	</listeners>
-
+	
 	<groups>
 		<exclude>
 			<group>sanitychecks</group>
diff --git a/web.config b/web.config
index a04afa1c..1d956b52 100644
--- a/web.config
+++ b/web.config
@@ -1,5 +1,17 @@
-<?xml version="1.0" encoding="utf-8"?>
 <configuration>
 	<system.webServer>
+		<security>
+			<requestFiltering>
+				<hiddenSegments>
+					<add segment="silverstripe-cache/" />
+					<add segment="vendor" />
+					<add segment="composer.json" />
+					<add segment="composer.lock" />
+				</hiddenSegments>
+				<fileExtensions allowUnlisted="true" >
+					<add fileExtension=".ss" allowed="false"/>
+				</fileExtensions>
+			</requestFiltering>
+		</security>
 	</system.webServer>
 </configuration>
\ No newline at end of file