Session Report

Summary:

Test run at: 2017-04-10 07:40:19 GMT
Client Prefix (v4): 140.112.238.x/24
Client AS (v4): 17716 (NTU-TW)
IPv4 Probes: 89

Outbound spoofing summary (from the client to our server)
Source address type	IPv4
Private - RFC1918	rewritten
Routable	rewritten
Largest spoofable neighbor prefix length	none

Spoof status key
received		Spoofed packet was received.	✔	Pattern of tests from this IP block indicates a switch from allowing spoofing to blocking it.
rewritten		Spoofed packet was received, but the source address was changed en route.
blocked		Spoofed packet was not received, but unspoofed packet was.
unknown		Neither spoofed nor unspoofed packet was received.

Warnings:

• ⚠️ Your host is behind a Network Address Translation (NAT) router or firewall which rewrites the source addresses of the test traffic. To test your provider's network further, you must remove the NAT/firewall/router and connect directly.

IPv4 AS Route:

This test run probed the following paths in order to infer your ability to send different spoofed source packets. Each node in the graph corresponds to an autonomous system, i.e. different Internet service providers. NOTE: This graph does NOT show if an AS blocks spoofed packets, only the path taken by received spoofed packets. The IP Path Details are available for this run. If non-spoofed packets weren't received at a destination, the traceroute to that destination is not included in this graph and may even cause a totally empty graph.

IPv4 Adjacent Netblock Testing:

Your host (140.112.238.x/24) can spoof 0 neighboring addresses

Spoofed source address (anon)	Prefix Length	ASN of spoofed source address	Received
140.112.238.x/24	/31	17716	rewritten
140.112.238.x/24	/30	17716	rewritten
140.112.238.x/24	/29	17716	rewritten
140.112.238.x/24	/28	17716	rewritten
140.112.238.x/24	/27	17716	rewritten
140.112.238.x/24	/26	17716	rewritten
140.112.238.x/24	/25	17716	rewritten
140.112.238.x/24	/24	17716	rewritten
140.112.239.x/24	/23	17716	rewritten
140.112.236.x/24	/22	17716	rewritten
140.112.234.x/24	/21	17716	rewritten
140.112.230.x/24	/20	17716	rewritten
140.112.254.x/24	/19	17716	rewritten
140.112.206.x/24	/18	17716	rewritten
140.112.174.x/24	/17	17716	rewritten
140.112.110.x/24	/16	17716	rewritten
140.113.238.x/24	/15	9916	rewritten
140.114.238.x/24	/14	18047	rewritten
140.116.238.x/24	/13	1659	rewritten
140.120.238.x/24	/12	1659	rewritten
140.96.238.x/24	/11	18422	rewritten
140.80.238.x/24	/10	27293	rewritten
140.48.238.x/24	/9	UNROUTED	rewritten
140.240.238.x/24	/8	4134	rewritten

Meaning of status in Received column:

rewritten

The source address of the probe packets we received differs from the spoofed address. It appears that an intermediate device is rewriting your packet headers.

IPv4 Outbound Filtering Depth:

The tracefilter test found your host unable to spoof routable, non-adjacent source addresses through even the first IP hop.

Summary:

The results from all tests are aggregated to produce a summary "State of IP Spoofing" report.

Feedback:

We welcome questions and feedback to the Spoofer Information Mailing List and invite users to join the Spoofer Users Mailing List for discussion and announcements.