[FUG-BR] SYNCOOKIE authentication, segment rejected

[Thiago Gomes]

Galera,

Estou recebendo essas messagens no meu DNS..

Nov 26 01:33:41 ns2 kernel: TCP: [118.107.200.130]:85 to
[222.222.222.222]:53 tcpflags 0x10<ACK>; syncache_expand: Segment
failed SYNCOOKIE authentication, segment rejected (probably spoofed)
Nov 26 01:33:41 ns2 kernel: TCP: [118.107.200.2]:84 to
[222.222.222.222]:53 tcpflags 0x10<ACK>; syncache_expand: Segment
failed SYNCOOKIE authentication, segment rejected (probably spoofed)
Nov 26 01:33:41 ns2 kernel: TCP: [61.4.111.122]:83 to
[222.222.222.222]:53 tcpflags 0x10<ACK>; syncache_expand: Segment
failed SYNCOOKIE authentication, segment rejected (probably spoofed)
Nov 26 01:33:41 ns2 kernel: TCP: [58.26.156.2]:81 to
[222.222.222.222]:53 tcpflags 0x10<ACK>; syncache_expand: Segment
failed SYNCOOKIE authentication, segment rejected (probably spoofed)
Nov 26 01:33:41 ns2 kernel: TCP: [58.26.156.130]:82 to
[222.222.222.222]:53 tcpflags 0x10<ACK>; syncache_expand: Segment
failed SYNCOOKIE authentication, segment rejected (probably spoofed)

Alguqem sabe com mais detalhes o que isso significa e o que mais
acarretar.. posso evitar isso ??