diff --git a/oisf.yaml b/oisf.yaml
index 9f139851ee..4ed278a59e 100644
--- a/oisf.yaml
+++ b/oisf.yaml
@@ -96,7 +96,7 @@ vars:
 
     HTTP_PORTS: "80:81,88"
 
-    SHELLCODE_PORTS: 80
+    SHELLCODE_PORTS: "!80"
 
     ORACLE_PORTS: 1521