Session Report
Test run at: 2026-06-25 16:08:08 GMT
Client Prefix (v4): 37.99.123.x/24
Client AS (v4): 21299 (KAR-TEL-AS)
IPv4 Probes: 162
Outbound spoofing summary (from the client to our server) Source address type IPv4 Private - RFC1918 unknown Routable unknown 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 was unable to source even non-spoofed IPv4 UDP traffic to our servers. A firewall, router or other middlebox is preventing our testing. To test your provider's network further, you must remove the firewall or router and connect directly.
- ⚠️ The spoofer client was unable to send spoofed headers due to an operating system restriction.
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 (37.99.123.x/24) can spoof 0 neighboring addresses
Spoofed source address (anon) Prefix
LengthASN of spoofed
source addressReceived 37.99.123.x/24 /31 21299 sendto 37.99.123.x/24 /30 21299 sendto 37.99.123.x/24 /29 21299 sendto 37.99.123.x/24 /28 21299 sendto 37.99.123.x/24 /27 21299 sendto 37.99.123.x/24 /26 21299 sendto 37.99.123.x/24 /25 21299 sendto 37.99.123.x/24 /24 21299 sendto 37.99.122.x/24 /23 21299 sendto 37.99.121.x/24 /22 21299 sendto 37.99.127.x/24 /21 21299 sendto 37.99.115.x/24 /20 21299 sendto 37.99.107.x/24 /19 21299 sendto 37.99.91.x/24 /18 21299 sendto 37.99.59.x/24 /17 21299 sendto 37.99.251.x/24 /16 45015 sendto 37.98.123.x/24 /15 UNROUTED sendto 37.97.123.x/24 /14 9009 sendto 37.103.123.x/24 /13 1267 sendto 37.107.123.x/24 /12 25019 sendto 37.115.123.x/24 /11 15895 sendto 37.67.123.x/24 /10 15557 sendto 37.35.123.x/24 /9 15600 sendto 37.227.123.x/24 /8 24608 sendto Meaning of status in Received column:
sendto The spoofer client was unable to send spoofed headers due to an operating system restriction.
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:
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