It looks more like data corruption of various forms as opposed to a fault in checksumming:
- Truncation of some layer-4 data including headers to 75 octets
- Some bad TCP packets have stored header lengths of 0 octets
- I often see lines of incrementing bytes (30 31 32 etc.). For example, packet 962 has a train of values from 0x10 to 0x2f, starting at position 0x003a (the TCP timestamps). I think these are meant to be fragments from the ping packets (which contain 8 octets then values 0x10 to 0x37), but these are straying into non-ICMP packets.
- There are pieces of HTTP in non-HTTP protocols. For example, packet 1394 is supposed to be UDP, but looks like it is really TCP traffic with the wrong protocol number. The checksum is still invalid in either case.
- It is possible to corrupt layer-4 checksums only, leaving the IP layer untouched.