Portal Home > Knowledgebase > Transparency Report > 06/08/2014 [SPAM] Nuclearfallout, Enterprises, Inc @ U.S. Texas 5 (161)

06/08/2014 [SPAM] Nuclearfallout, Enterprises, Inc @ U.S. Texas 5 (161)

Original report:

You appear to be running an open SNMP server at IP address 173.255.139.136 that
participated in an attack against a customer of ours today, generating large UDP
responses to spoofed queries, with those responses becoming fragmented because
of their size.

Please consider reconfiguring your SNMP system in one or more of these ways:

- Block queries made by unauthorized addresses. This can be done with an ACL or
other firewall rule.
- Use a different query string than "public" and which cannot be
easily guessed by a 3rd party.
- Disable SNMP entirely.

If you are an ISP, please also look at your network configuration and make sure
that you do not allow spoofed traffic (that pretends to be from external IP
addresses) to leave the network. Hosts that allow spoofed traffic make possible
this type of attack.

Example SNMP responses sent to us by your device during the attack are given
below.
Timestamps (far left) are PDT (UTC-7), and the date is 2014-08-01.

20:52:21.522238 IP (tos 0x0, ttl 56, id 0, offset 0, flags [DF], proto UDP (17),
length 1214) 173.255.139.136.161 > 74.91.113.x.3659: UDP, length 1186
0x0000: 4500 04be 0000 4000 3811 48cc adff 8b88 E.....@.8.H.....
0x0010: 4a5b 7180 00a1 0e4b 04aa f899 3082 049e J[q....K....0...
0x0020: 0201 0104 0670 7562 6c69 63a2 8204 8f02 .....public.....
0x0030: 024e 4702 0100 0201 0030 8204 8130 6606 .NG......0...0f.
0x0040: 082b 0601 0201 0101 0004 5a4c 696e 7578 .+........ZLinux
0x0050: 2077 .w
20:52:21.694174 IP (tos 0x0, ttl 56, id 0, offset 0, flags [DF], proto UDP (17),
length 1214) 173.255.139.136.161 > 74.91.113.x.3659: UDP, length 1186
0x0000: 4500 04be 0000 4000 3811 48cc adff 8b88 E.....@.8.H.....
0x0010: 4a5b 7180 00a1 0e4b 04aa d699 3082 049e J[q....K....0...
0x0020: 0201 0104 0670 7562 6c69 63a2 8204 8f02 .....public.....
0x0030: 024e 4702 0100 0201 0030 8204 8130 6606 .NG......0...0f.
0x0040: 082b 0601 0201 0101 0004 5a4c 696e 7578 .+........ZLinux
0x0050: 2077 .w

(The final octet of our customer's IP address is masked in the above output
because some automatic parsers become confused when multiple IP addresses are
included. The value of that octet is "128".)


Action that has been taken from Proxy.sh: Because the server is located in a jurisdiction with precise intellectual property laws, we have reset accounts who forwarded port 161 (nothing may identify a single account) and we have blocked port 161 via Firewall.

Related Knowledgebase Articles