1 diff --git a/scapy/contrib/cdp.py b/scapy/contrib/cdp.py
2 index 9ad15c8a..d9cd08c6 100644
3 --- a/scapy/contrib/cdp.py
4 +++ b/scapy/contrib/cdp.py
5 @@ -357,7 +357,7 @@ class _CDPChecksum:
6 This padding is only used for checksum computation. The original
7 packet should not be altered."""
10 + last_chr = pkt[len(pkt)-1:]
11 if last_chr <= b'\x80':
12 return pkt[:-1] + b'\x00' + last_chr