diff --git a/src/plugins/cdp/test/test_cdp.py b/src/plugins/cdp/test/test_cdp.py
index c0e5287..27f35c2 100644
--- a/src/plugins/cdp/test/test_cdp.py
+++ b/src/plugins/cdp/test/test_cdp.py
@@ -98,13 +98,9 @@
         self.assert_equal(system[:length], self.device_id[:length],
                           "CDP received invalid device id")
 
-    @unittest.skipIf(sys.version_info[0] > 2,
-                     "not supported in python3/scapy")
     def test_cdp_underflow_tlv(self):
         self.send_bad_packet(3, ".")
 
-    @unittest.skipIf(sys.version_info[0] > 2,
-                     "not supported in python3/scapy")
     def test_cdp_overflow_tlv(self):
         self.send_bad_packet(8, ".")
 
diff --git a/test/patches/scapy-2.4/cdp.patch b/test/patches/scapy-2.4/cdp.patch
index 3248915..de16f5d 100644
--- a/test/patches/scapy-2.4/cdp.patch
+++ b/test/patches/scapy-2.4/cdp.patch
@@ -12,7 +12,7 @@
                      StrLenField("val", "", length_from=lambda x:x.len - 4) ]
  
  
-@@ -178,7 +179,8 @@ class CDPMsgAddr(CDPMsgGeneric):
+@@ -178,5 +179,6 @@ class CDPMsgAddr(CDPMsgGeneric):
  class CDPMsgPortID(CDPMsgGeneric):
      name = "Port ID"
      fields_desc = [ XShortEnumField("type", 0x0003, _cdp_tlv_types),
@@ -20,5 +20,12 @@
 +                    FieldLenField("len", None, "iface", "!H",
 +                                  adjust=lambda pkt, x: x + 4),
                      StrLenField("iface", "Port 1", length_from=lambda x:x.len - 4) ]
- 
- 
+@@ -319,7 +319,7 @@ class _CDPChecksum:
+         This padding is only used for checksum computation.  The original
+         packet should not be altered."""
+         if len(pkt) % 2:
+-            last_chr = pkt[-1]
++            last_chr = pkt[len(pkt)-1:]
+             if last_chr <= b'\x80':
+                 return pkt[:-1] + b'\x00' + last_chr
+             else: