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Unable to capture UDP scan packets

0

Hi all, I am trying to inject udp scan packets from Kali box to target machine using following command.

[email protected]#nc -unvv -w 1 -z <ip address=""> <port>

nc:<ip address=""> <port> is open nc:using datagram socket

The scan is successful but i am not able to see the packets on Wireshark running on Kali. Whereas able to see TCP connectscan packets.

asked 08 May '14, 11:23

krishnayeddula's gravatar image

krishnayeddula
629354148
accept rate: 6%

No bridging. Same Host.

On tgt [[email protected] ~]# ifconfig

**eth0 Link encap:Ethernet HWaddr**

      inet addr:A.B.C.D  Bcast:A.B.C.E  Mask:255.255.255.0

On Kali initiator

[[email protected] ~]# ifconfig

eth0 Link encap:Ethernet HWaddr

      inet addr:A.B.C.G  Bcast:A.B.C.E  Mask:255.255.255.0
(12 May '14, 15:59) krishnayeddula

One Answer:

0

As you did not mention the important things, I'm going to guess....

1.) Did you send the traffic to the same system (localhost)?

If so, you won't see that traffic on eth0/eth1/ethx. Instead you should capture on the loopback interface: lo

2.) Did you send the traffic to another system, via the LAN interface?

If so: Where and how exactly did you try to capture the traffic?

3.) Do you see the traffic, if you capture with tcpdump?

tcpdump -ni eth0 udp port 8888

Please replace 8888 with whatever port you are using in your test.

Regards
Kurt

answered 09 May '14, 11:23

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%

edited 09 May '14, 11:34

Thanks for the reply Kurt. I will perform the test as suggested but why i am seeing tcp packets but not udp? BTW both Initiator and target are virtual machine instances and interface is eth0.

(11 May '14, 11:09) krishnayeddula

both Initiator and target are virtual machine instances and interface is eth0

Same VM host or different one? Bridged interface or other?

(11 May '14, 16:05) Kurt Knochner ♦