diff --git a/mantis/src/detection/ml/server_ports.rs b/mantis/src/detection/ml/server_ports.rs
index 050d89a..e616c97 100644
--- a/mantis/src/detection/ml/server_ports.rs
+++ b/mantis/src/detection/ml/server_ports.rs
@@ -124,11 +124,12 @@ pub fn is_non_unicast(ip: &str) -> bool {
     };
     match addr {
         IpAddr::V4(v4) => {
-            v4.is_multicast()     // 224.0.0.0/4
-                || v4.is_broadcast()  // 255.255.255.255
-                || v4.is_loopback()   // 127.0.0.0/8
-                || v4.is_unspecified() // 0.0.0.0
-                || v4.is_link_local() // 169.254.0.0/16
+            v4.is_multicast()       // 224.0.0.0/4
+                || v4.is_broadcast()    // 255.255.255.255
+                || v4.is_loopback()     // 127.0.0.0/8
+                || v4.is_unspecified()  // 0.0.0.0
+                || v4.is_link_local()   // 169.254.0.0/16
+                || v4.octets()[3] == 255 // subnet-directed broadcast (x.x.x.255)
         }
         IpAddr::V6(v6) => {
             v6.is_multicast()      // ff00::/8