TCP SYN (JA4T)

65535_2-4-8-1-3_1440_8

first seen 2026-07-01 14:38 · last seen 2026-09-16 19:53 · JSON

Last 7 days (12 observations)

Distinct clients per day (last 30 days, peak 36/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 window65535
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
t13d4412h1_fd39b124ee10_58ed7828516f243
t13d1515h1_8daaf6152771_de4a06bb82e3127
t13d1515h1_8daaf6152771_0a20fe35d3a595
t13d1516h2_8daaf6152771_806a8c22fdea Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 151.0.7922.137, chromium 151.0.7922.34, +24 more.The fingerprint page shows the full measured match list. More on the catalog.26
t13d1516h2_8daaf6152771_d8a2da3f94cd Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.14
t13d1516h1_8daaf6152771_1a63afa7c4786
t13d1513h2_8daaf6152771_eca864cca44a4
t13d3013h2_1d37bd780c83_8537cf56674e3
t13d2013h1_2b729b4bf6f3_e24568c0d4403
t13d1515h2_8daaf6152771_e8ed158c4d852

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn050000_b223a0ebb0b5_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: python-requests 2.34.2, python-requests 2.33.1, python-requests 2.32.3.The fingerprint page shows the full measured match list. More on the catalog.243
ge11nn13enus_9db22d02e17a_000000000000_000000000000169
ge11nn14enus_4a2973d235de_000000000000_00000000000059
ge20nr13engb_2e13211475bf_000000000000_00000000000015
ge20nr13enus_2e13211475bf_000000000000_0000000000007
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.18.0, +9 more.The fingerprint page shows the full measured match list. More on the catalog.6
ge20nn030000_80b089f68b8e_000000000000_0000000000005
ge20nr13enus_762281698773_000000000000_0000000000003
ge11nn030000_fe444ad14866_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.16.0.The fingerprint page shows the full measured match list. More on the catalog.3
ge20nr13enus_b3e540f310f0_000000000000_0000000000002

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:110|m,a,s,p27
4:16777216|16711681|0|m,p,a,s6
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:183|m,a,s,p6
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +43 more.The fingerprint page shows the full measured match list. More on the catalog.5
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 149.0.7827.102, +59 more.The fingerprint page shows the full measured match list. More on the catalog.4
3:100;4:65536;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, curl 8.18.0, curl 8.21.0, +7 more.The fingerprint page shows the full measured match list. More on the catalog.4
3:100;4:10485760;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0.The fingerprint page shows the full measured match list. More on the catalog.2
1:4096;2:0;4:32768;5:16384|12517377|3:0:0:22|m,p,a,s2

TCP SYN (p0f)

fingerprintco-occurrences
4:46+18:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:077
4:47+17:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:060
4:45+19:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:059
4:48+16:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:033
4:44+20:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:032
4:49+15:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:026
4:43+21:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:023
4:42+22:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:021
4:51+13:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:016
4:41+23:0:1440:65535,8:mss,sok,ts,nop,ws:df,id+:016

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.51 Safari/537.3626
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/104.0.0.0 Safari/537.3622
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.3620
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.3619
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/101.0.4951.67 Safari/537.3619
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.3618
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.3616
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3615
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.3614
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.3614

Country

fingerprintco-occurrences
BD · Bangladesh142
BR · Brazil102
US · United States49
PK · Pakistan45
ZA · South Africa35
GB · United Kingdom23
RU · Russia22
CO · Colombia13
UA · Ukraine9
AR · Argentina7

Network (ASN)

fingerprintco-occurrences
AS15169 · Google LLC33
AS9541 · Cyber Internet Services (Pvt) Ltd.23
AS7922 · Comcast Cable Communications, LLC16
AS11845 · Vox Telecom Ltd11
AS5607 · Sky UK Limited11
AS3816 · COLOMBIA TELECOMUNICACIONES S.A. ESP BIC10
AS12389 · PJSC Rostelecom8
AS14593 · Space Exploration Technologies Corporation6
AS18881 · TELEFÔNICA BRASIL S.A6
AS22927 · Telefonica de Argentina6

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprintlinked observations
q13d0311h3_55b375c5d22e_653d80c3fe9d2
q13d0315h3_55b375c5d22e_dc5437974b472