Session Report

Summary:

Test run at: 2023-01-05 14:32:24 GMT
Client Prefix (v4): 138.204.140.x/24
Client AS (v4): 263903
IPv4 Probes: 60

Outbound spoofing summary (from the client to our server)
Source address type	IPv4
Private - RFC1918	rewritten
Routable	✔	received
Largest spoofable neighbor prefix length	/23

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 (138.204.140.x/24) can spoof 511 neighboring addresses (within your /23 prefix)

Spoofed source address (anon)	Prefix Length	ASN of spoofed source address	Received
138.204.140.x/24	/31	263903	no
138.204.140.x/24	/30	263903	no
138.204.140.x/24	/29	263903	rewritten
138.204.140.x/24	/28	263903	rewritten
138.204.140.x/24	/27	263903	rewritten
138.204.140.x/24	/26	263903	rewritten
138.204.140.x/24	/25	263903	rewritten
138.204.140.x/24	/24	263903	rewritten
138.204.141.x/24	/23	263903	yes
138.204.142.x/24	/22	263903	rewritten
138.204.136.x/24	/21	28210	rewritten
138.204.132.x/24	/20	263888	rewritten
138.204.156.x/24	/19	263687	rewritten
138.204.172.x/24	/18	263911	rewritten
138.204.204.x/24	/17	UNROUTED	rewritten
138.204.12.x/24	/16	41095	rewritten
138.205.140.x/24	/15	UNROUTED	rewritten
138.206.140.x/24	/14	10100	rewritten
138.200.140.x/24	/13	UNROUTED	rewritten
138.196.140.x/24	/12	UNROUTED	rewritten
138.220.140.x/24	/11	10497	rewritten
138.236.140.x/24	/10	17234	rewritten
138.140.140.x/24	/9	721	rewritten
138.76.140.x/24	/8	UNROUTED	rewritten

Meaning of status in Received column:

no	Packets spoofed from adjacent netblock were not received, probably due to blocking
yes	Packets spoofed from adjacent netblock were received (but that netblock is within the source AS)
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 able to spoof routable, non-adjacent source addresses through the first 10 IP hop(s).

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.