TCP SYN (p0f)

4:39+25:0:1440:mss*44,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-10-03 14:00 · last seen 2026-10-03 14:00 · 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 TTL39+25
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_f50d94e863eb Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.1, go-net/http 1.27.3, go-net/http 1.27.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
po11nn090000_d19993cb819f_000000000000_0000000000001

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1440_101

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.4 Safari/605.1.151

Country

fingerprintco-occurrences
BR · Brazil1

Network (ASN)

fingerprintco-occurrences
AS8075 · Microsoft Corporation1