TCP SYN (p0f)

4:40+24:0:1440:mss*44,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-09-30 09:34 · last seen 2026-10-02 15:26 · JSON

Distinct clients per day (last 30 days, peak 1/day)

Distinct clients are counted by IP-hash per complete UTC day — unlike observation counts this is insensitive to one chatty client, but NAT merges clients and address rotation splits them.

Decomposed attributes

IP version4
Initial TTL40+24
Options length0
MSS1440
Window sizemss*44
Window scale10
Options layoutmss,sok,ts,nop,ws
Quirksdf,id+
Payload class0

Co-observed signals

Signals from other families seen in the same observation. A fingerprint spread thinly across many lower-layer signatures is a classic inconsistency signal.

TLS ClientHello (JA4)

fingerprintco-occurrences
t13d131100_f57a46bbacb6_ab7e3b40a677 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.5, go-net/http 1.26.4.The fingerprint page shows the full measured match list. More on the catalog.2
t13d1312h2_f57a46bbacb6_f50d94e863eb Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.1, go-net/http 1.27.0, go-net/http 1.27.3, +1 more.The fingerprint page shows the full measured match list. More on the catalog.2

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn06enus_aeac3047b50b_000000000000_0000000000002
he20nn010000_a510e5066512_000000000000_0000000000001
po20nn070000_d9e5c720862d_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
2:0;4:4194304;5:1048576;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.1, go-net/http 1.27.0, go-net/http 1.27.3, +1 more.The fingerprint page shows the full measured match list. More on the catalog.2

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1440_104

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/121.02
Go-http-client/2.01
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.113 Safari/537.36 Assetnote/1.0.01

Country

fingerprintco-occurrences
BR · Brazil4

Network (ASN)

fingerprintco-occurrences
AS8075 · Microsoft Corporation4