diff --git a/web/src/main/java/org/springframework/security/web/firewall/FirewalledResponse.java b/web/src/main/java/org/springframework/security/web/firewall/FirewalledResponse.java
index 95364af808..b7360091a0 100644
--- a/web/src/main/java/org/springframework/security/web/firewall/FirewalledResponse.java
+++ b/web/src/main/java/org/springframework/security/web/firewall/FirewalledResponse.java
@@ -9,7 +9,7 @@ import java.util.regex.Pattern;
  * @author Luke Taylor
  */
 class FirewalledResponse extends HttpServletResponseWrapper {
-    Pattern CR_OR_LF = Pattern.compile("\\r|\\n");
+    private static final Pattern CR_OR_LF = Pattern.compile("\\r|\\n");
 
     public FirewalledResponse(HttpServletResponse response) {
         super(response);