TCP SYN (JA4T)

42340_2-4-8-1-3_1460_9

first seen 2026-06-30 18:55 · last seen 2026-10-30 10:40 · JSON

Last 7 days (20 observations)

Distinct clients per day (last 30 days, peak 281/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 window42340
Option kinds2-4-8-1-3
MSS1460
Window scale9

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
t13d151100_8daaf6152771_ab7e3b40a677393
t13d3013h2_1d37bd780c83_8537cf56674e Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.18.0.The fingerprint page shows the full measured match list. More on the catalog.303
t13d3515h1_8f004308c246_5c2c66f702b0225
t13d191000_9dc949149365_e7c285222651154
t13d1312h1_f57a46bbacb6_ab7e3b40a677117
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.91
t13d311200_e8f1e7e78f70_d339722ba4af71
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.54
t13d301300_1d37bd780c83_5ae85263eb3b28
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.25

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_000000000000302
ge11nn050000_a1c329e38462_000000000000_000000000000174
ge11nn06enus_3ce581af28ff_000000000000_00000000000099
ge11nn05zh00_4ee89fec50ea_000000000000_00000000000080
po11nn080000_86f5668e3d93_000000000000_00000000000058
ge11nn05zh00_ddc401472a00_000000000000_00000000000029
ge11nr39enus_1c19b8b5959c_000000000000_00000000000027
ge11nr120000_310be72a5e7f_000000000000_00000000000025
ge11nr38enus_c9f28418db6b_000000000000_00000000000024
ge20nn04enus_989c7cc05c9b_000000000000_00000000000024

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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, +8 more.The fingerprint page shows the full measured match list. More on the catalog.303
1:65536;2:0;4:6291456;6:262144;4:1048576|15663105|1:0:0:256|m,a,s,p24
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 152.0.7977.83, +85 more.The fingerprint page shows the full measured match list. More on the catalog.17
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, +60 more.The fingerprint page shows the full measured match list. More on the catalog.14
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 1.27.3, go-net/http 1.27.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.9
1:65536;2:0;4:6291456;6:262144|15663105|3:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 151.0.7922.34, chromium 147.0.7727.15, chromium 145.0.7632.6, +26 more.The fingerprint page shows the full measured match list. More on the catalog.5
1:65536;2:0;4:6291456;6:262144|15663105|5:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 133.0.6943.16, chrome 156.0.8078.48, chrome 150.0.7871.128, +3 more.The fingerprint page shows the full measured match list. More on the catalog.5
1:65536;3:1000;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p1
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.1
1:65536;2:0;4:6291456;6:262144|15663105|7:1:0:256|m,a,s,p1

TCP SYN (p0f)

fingerprintco-occurrences
4:54+10:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0389
4:55+9:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0279
4:56+8:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0213
4:49+15:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0122
4:47+17:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0111
4:51+13:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0110
4:57+7:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:079
4:53+11:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:078
4:50+14:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:060
4:46+18:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:055

User-Agent

fingerprintco-occurrences
curl/8.14.1302
Mozilla/5.0 (compatible; Infrawatch/1.0; +https://infrawat.ch/)232
StartmeBot/1.0 (+https://start.me/bot)99
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3671
Mozilla/5.0 (Linux; Android 11; vivo 1906; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/87.0.4280.141 Mobile Safari/537.36 VivoBrowser/8.9.0.063
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.3640
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.3632
curl/7.4.029
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/148.0.0.0 Safari/537.3624
Mozilla/5.0 (Linux; U; Android 14; en-US; Redmi Note 13 Pro Build/UP1A.231005.007) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 UCBrowser/13.4.0.1306 Mobile Safari/537.3622

Country

fingerprintco-occurrences
US · United States632
GB · United Kingdom261
NL · Netherlands224
DE · Germany199
CN · China136
SE · Sweden61
PL · Poland20
LV · Latvia12
HK · Hong Kong SAR China9
CH · Switzerland6

Network (ASN)

fingerprintco-occurrences
AS150303 · SoloRDP318
AS25369 · Hydra Communications Ltd232
AS14061 · DigitalOcean, LLC203
AS142430 · DIGI VPS168
AS4134 · CHINANET BACKBONE136
AS48090 · TECHOFF SRV LIMITED113
AS14618 · Amazon.com, Inc.99
AS215703 · FREAKHOSTING LTD70
AS203861 · Miteflux Technologies Ltd58
AS218785 · TC DATACENTER LIMITED18

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,001e,0018,0019,0100,0101 Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1, python-requests 2.34.2, curl 8.23.0, +4 more.The fingerprint page shows the full measured match list. More on the catalog.313
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.19
001d,0017,001e,0019,0018,0100,0101,0102,0103,0104 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, php-guzzle 8.3.1, curl 7.88.1, +10 more.The fingerprint page shows the full measured match list. More on the catalog.7
001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.4
11ec,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 158.0.1, firefox 157.0, firefox 157.0.1, +5 more.The fingerprint page shows the full measured match list. More on the catalog.1

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
q13d0312h3_55b375c5d22e_178839b6cec15