diff --git a/jetty-server/src/main/java/org/eclipse/jetty/server/ForwardedRequestCustomizer.java b/jetty-server/src/main/java/org/eclipse/jetty/server/ForwardedRequestCustomizer.java
index 7700e91e650..3dc313b49f0 100644
--- a/jetty-server/src/main/java/org/eclipse/jetty/server/ForwardedRequestCustomizer.java
+++ b/jetty-server/src/main/java/org/eclipse/jetty/server/ForwardedRequestCustomizer.java
@@ -36,8 +36,6 @@ import org.eclipse.jetty.util.ArrayTrie;
 import org.eclipse.jetty.util.HostPort;
 import org.eclipse.jetty.util.StringUtil;
 import org.eclipse.jetty.util.Trie;
-import org.eclipse.jetty.util.log.Log;
-import org.eclipse.jetty.util.log.Logger;
 
 import static java.lang.invoke.MethodType.methodType;
 
@@ -64,8 +62,6 @@ import static java.lang.invoke.MethodType.methodType;
  */
 public class ForwardedRequestCustomizer implements Customizer
 {
-    private static final Logger LOG = Log.getLogger(ForwardedRequestCustomizer.class);
-
     private HostPortHttpField _forcedHost;
     private boolean _proxyAsAuthority = false;
     private boolean _forwardedPortAsAuthority = true;
@@ -434,8 +430,7 @@ public class ForwardedRequestCustomizer implements Customizer
 
     protected void onError(HttpField field, Throwable t)
     {
-        LOG.warn("Exception while processing {}", field, t);
-        throw new BadMessageException("Bad header value for " + field.getName());
+        throw new BadMessageException("Bad header value for " + field.getName(), t);
     }
 
     protected String getLeftMost(String headerValue)
diff --git a/jetty-server/src/test/java/org/eclipse/jetty/server/ForwardedRequestCustomizerTest.java b/jetty-server/src/test/java/org/eclipse/jetty/server/ForwardedRequestCustomizerTest.java
index a6dfa9f58a2..a55fcf82ef4 100644
--- a/jetty-server/src/test/java/org/eclipse/jetty/server/ForwardedRequestCustomizerTest.java
+++ b/jetty-server/src/test/java/org/eclipse/jetty/server/ForwardedRequestCustomizerTest.java
@@ -32,6 +32,7 @@ import org.eclipse.jetty.http.HttpTester;
 import org.eclipse.jetty.server.handler.AbstractHandler;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
@@ -619,6 +620,25 @@ public class ForwardedRequestCustomizerTest
         expectations.accept(actual);
     }
 
+    @Test
+    public void testBadInput() throws Exception
+    {
+        Request request = new Request("Bad port value")
+            .headers(
+                "GET / HTTP/1.1",
+                "Host: myhost",
+                "X-Forwarded-Port: "
+            );
+
+        request.configure(customizer);
+
+        String rawRequest = request.getRawRequest((header) -> header);
+        System.out.println(rawRequest);
+
+        HttpTester.Response response = HttpTester.parseResponse(connector.getResponse(rawRequest));
+        assertThat("status", response.getStatus(), is(400));
+    }
+
     private static class Request
     {
         String description;