diff --git a/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdRequest.java b/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdRequest.java
index 6411cb75a9..dfcdad8768 100644
--- a/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdRequest.java
+++ b/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdRequest.java
@@ -63,7 +63,7 @@ public final class SocksCmdRequest extends SocksRequest {
             case UNKNOWN:
                 break;
         }
-        if (port < 0 && port >= 65536) {
+        if (port <= 0 || port >= 65536) {
             throw new IllegalArgumentException(port + " is not in bounds 0 < x < 65536");
         }
         this.cmdType = cmdType;
diff --git a/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdResponse.java b/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdResponse.java
index 567ceb63ff..b38db62121 100644
--- a/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdResponse.java
+++ b/codec-socks/src/main/java/io/netty/handler/codec/socks/SocksCmdResponse.java
@@ -90,7 +90,7 @@ public final class SocksCmdResponse extends SocksResponse {
             }
             host = IDN.toASCII(host);
         }
-        if (port < 0 && port >= 65535) {
+        if (port <= 0 && port >= 65536) {
             throw new IllegalArgumentException(port + " is not in bounds 0 < x < 65536");
         }
         this.cmdStatus = cmdStatus;
diff --git a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksAuthResponseTest.java b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksAuthResponseTest.java
index 0c15941327..cde19e2c34 100644
--- a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksAuthResponseTest.java
+++ b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksAuthResponseTest.java
@@ -27,4 +27,5 @@ public class SocksAuthResponseTest {
             assertTrue(e instanceof NullPointerException);
         }
     }
+
 }
diff --git a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestDecoderTest.java b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestDecoderTest.java
index 350461bd26..0672453cd7 100644
--- a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestDecoderTest.java
+++ b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestDecoderTest.java
@@ -51,7 +51,7 @@ public class SocksCmdRequestDecoderTest {
     @Test
     public void testCmdRequestDecoderIPv4() {
         String[] hosts = {"127.0.0.1", };
-        int[] ports = {0, 32769, 65535 };
+        int[] ports = {1, 32769, 65535 };
         for (SocksCmdType cmdType : SocksCmdType.values()) {
             for (String host : hosts) {
                 for (int port : ports) {
@@ -64,7 +64,7 @@ public class SocksCmdRequestDecoderTest {
     @Test
     public void testCmdRequestDecoderIPv6() {
         String[] hosts = {SocksCommonUtils.ipv6toStr(IPAddressUtil.textToNumericFormatV6("::1"))};
-        int[] ports = {0, 32769, 65535};
+        int[] ports = {1, 32769, 65535};
         for (SocksCmdType cmdType : SocksCmdType.values()) {
             for (String host : hosts) {
                 for (int port : ports) {
@@ -88,7 +88,7 @@ public class SocksCmdRequestDecoderTest {
                           "例え.テスト",
                           "실례.테스트",
                           "உதாரணம்.பரிட்சை"};
-        int[] ports = {0, 32769, 65535};
+        int[] ports = {1, 32769, 65535};
         for (SocksCmdType cmdType : SocksCmdType.values()) {
             for (String host : hosts) {
                 for (int port : ports) {
diff --git a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestTest.java b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestTest.java
index 5eb163c333..1fc0d9c199 100644
--- a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestTest.java
+++ b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdRequestTest.java
@@ -23,19 +23,19 @@ public class SocksCmdRequestTest {
     @Test
     public void testConstructorParamsAreNotNull() {
         try {
-            new SocksCmdRequest(null, SocksAddressType.UNKNOWN, "", 0);
+            new SocksCmdRequest(null, SocksAddressType.UNKNOWN, "", 1);
         } catch (Exception e) {
             assertTrue(e instanceof NullPointerException);
         }
 
         try {
-            new SocksCmdRequest(SocksCmdType.UNKNOWN, null, "", 0);
+            new SocksCmdRequest(SocksCmdType.UNKNOWN, null, "", 1);
         } catch (Exception e) {
             assertTrue(e instanceof NullPointerException);
         }
 
         try {
-            new SocksCmdRequest(SocksCmdType.UNKNOWN, SocksAddressType.UNKNOWN, null, 0);
+            new SocksCmdRequest(SocksCmdType.UNKNOWN, SocksAddressType.UNKNOWN, null, 1);
         } catch (Exception e) {
             assertTrue(e instanceof NullPointerException);
         }
@@ -44,7 +44,7 @@ public class SocksCmdRequestTest {
     @Test
     public void testIPv4CorrectAddress() {
         try {
-            new SocksCmdRequest(SocksCmdType.BIND, SocksAddressType.IPv4, "54.54.1111.253", 0);
+            new SocksCmdRequest(SocksCmdType.BIND, SocksAddressType.IPv4, "54.54.1111.253", 1);
         } catch (Exception e) {
             assertTrue(e instanceof IllegalArgumentException);
         }
@@ -53,7 +53,7 @@ public class SocksCmdRequestTest {
     @Test
     public void testIPv6CorrectAddress() {
         try {
-            new SocksCmdRequest(SocksCmdType.BIND, SocksAddressType.IPv6, "xxx:xxx:xxx", 0);
+            new SocksCmdRequest(SocksCmdType.BIND, SocksAddressType.IPv6, "xxx:xxx:xxx", 1);
         } catch (Exception e) {
             assertTrue(e instanceof IllegalArgumentException);
         }
@@ -66,7 +66,7 @@ public class SocksCmdRequestTest {
                     "παράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμή" +
                     "παράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμή" +
                     "παράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμή" +
-                    "παράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμή", 0);
+                    "παράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμήπαράδειγμα.δοκιμή", 1);
         } catch (Exception e) {
             assertTrue(e instanceof IllegalArgumentException);
         }
@@ -76,7 +76,7 @@ public class SocksCmdRequestTest {
     public void testValidPortRange() {
         try {
             new SocksCmdRequest(SocksCmdType.BIND, SocksAddressType.DOMAIN,
-                    "παράδειγμα.δοκιμήπαράδει", -1);
+                    "παράδειγμα.δοκιμήπαράδει", 0);
         } catch (Exception e) {
             assertTrue(e instanceof IllegalArgumentException);
         }
diff --git a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdResponseTest.java b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdResponseTest.java
index f8d69f138f..420c5108f7 100644
--- a/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdResponseTest.java
+++ b/codec-socks/src/test/java/io/netty/handler/codec/socks/SocksCmdResponseTest.java
@@ -123,4 +123,18 @@ public class SocksCmdResponseTest {
         assertArrayEquals("Generated response differs from expected", expected, actualBytes);
     }
 
+    @Test
+    public void testValidPortRange() {
+        try {
+            new SocksCmdResponse(SocksCmdStatus.SUCCESS, SocksAddressType.IPv4, "127.0.0", 0);
+        } catch (Exception e) {
+            assertTrue(e instanceof IllegalArgumentException);
+        }
+
+        try {
+            new SocksCmdResponse(SocksCmdStatus.SUCCESS, SocksAddressType.IPv4, "127.0.0", 65536);
+        } catch (Exception e) {
+            assertTrue(e instanceof IllegalArgumentException);
+        }
+    }
 }