TCP SYN (JA4T)

62587_2-4-8-1-3_1440_8

first seen 2026-10-24 21:35 · last seen 2026-10-26 20:59 · JSON

Last 7 days (12 observations)

Distinct clients per day (last 30 days, peak 8/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

TCP window62587
Option kinds2-4-8-1-3
MSS1440
Window scale8

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
t13d251100_b78ed14e2fd0_f50d94e863eb12

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn05enus_dff23709e538_000000000000_0000000000009
ge11nn050000_845398f9f2c0_000000000000_0000000000003

TCP SYN (p0f)

fingerprintco-occurrences
6:243+12:0:1440:62587,8:mss,sok,ts,nop,ws:flow:05
6:250+5:0:1440:62587,8:mss,sok,ts,nop,ws:flow:03
6:242+13:0:1440:62587,8:mss,sok,ts,nop,ws:flow:02
6:245+10:0:1440:62587,8:mss,sok,ts,nop,ws:flow:01
6:239+16:0:1440:62587,8:mss,sok,ts,nop,ws:flow:01

User-Agent

fingerprintco-occurrences
ApcosysBot/1.0 (+https://apcosys.net)12

Country

fingerprintco-occurrences
US · United States3
BR · Brazil2
SE · Sweden2
DE · Germany1
JP · Japan1
GB · United Kingdom1
FR · France1
IE · Ireland1

Network (ASN)

fingerprintco-occurrences
AS16509 · Amazon.com, Inc.11
AS14618 · Amazon.com, Inc.1

TLS supported groups

fingerprintco-occurrences
11ec,11eb,11ed,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.3, go-net/http 1.26.10.The fingerprint page shows the full measured match list. More on the catalog.12