It indicates a attacker attempted a Denial of Service attack against TCPDump. TCPDump is vulnerable to a Denial of Service if a malicious attacker sends a packet containing 0xff,0x02 bytes to UDP port 1701. Such a packet will cause the service to crash.
LBL tcpdump 3.8.1 and earlier versions.
Denial of Service
Apply appropriate patch from the vendor or Upgrade to non-vulnerable version if available.