TCP SYN (JA4T)

64240_2-4-8-1-3_1460_10

first seen 2026-06-29 22:24 · last seen 2026-11-01 20:28 · JSON

Last 7 days (86 observations)

Distinct clients per day (last 30 days, peak 156/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 window64240
Option kinds2-4-8-1-3
MSS1460
Window scale10

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
t13d141100_cbb2034c60b8_e5728521abd4363
t13d1712h1_ab0a1bf427ad_8e6e362c5eac205
t13d101000_61a7ad8aa9b6_3ea2f44fd1af189
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.164
t13d141000_cbb2034c60b8_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.22.12.The fingerprint page shows the full measured match list. More on the catalog.146
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.143
t13d4113h2_8ae0994cad11_86f67be995ff138
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, +28 more.The fingerprint page shows the full measured match list. More on the catalog.85
t13d1617h2_86a278354501_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.3, +10 more.The fingerprint page shows the full measured match list. More on the catalog.76
t13d1517h2_8daaf6152771_cb7bf5808d99 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 152.0.7977.83, chrome 156.0.8078.48, chrome 154.0.8037.57, +27 more.The fingerprint page shows the full measured match list. More on the catalog.64

HTTP request (JA4H)

fingerprintco-occurrences
ge11nr06enus_aeac3047b50b_000000000000_000000000000282
ge11nn050000_a1c329e38462_000000000000_000000000000220
ge11nn050000_fdb72fc7d4c1_000000000000_000000000000189
ge11nn10engb_ec5486a7d5a7_000000000000_000000000000185
ge20nn030000_bf75ddd0bb29_000000000000_000000000000159
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.137
ge20nn04enus_989c7cc05c9b_000000000000_000000000000115
ge20nr12engb_54b4638ab28b_000000000000_00000000000085
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.75
ge20nr12enus_a72b71f519fc_000000000000_00000000000067

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.308
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.147
1:65536;2:0;4:6291456;6:262144;4:1048576|15663105|1:0:0:256|m,a,s,p115
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.86
4:16777216|16711681|0|m,p,a,s71
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 155.0.1, +32 more.The fingerprint page shows the full measured match list. More on the catalog.67
2:0;4:4194304;5:16384;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.10, go-net/http 1.26.9, +8 more.The fingerprint page shows the full measured match list. More on the catalog.40
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:42|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 152.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.39
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.27
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.22

TCP SYN (p0f)

fingerprintco-occurrences
4:51+13:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0542
4:55+9:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0310
4:48+16:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0262
4:54+10:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0257
4:50+14:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0240
4:43+21:0:1460:mss*44,10:mss,sok,ts,nop,ws::0190
4:47+17:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0176
4:49+15:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0126
4:56+8:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0122
4:53+11:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:077

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36506
uk-nhs-data/0.0 (internal fraud-research)194
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36189
curl/8.14.1160
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36122
Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.091
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.3659
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.050
curl/8.5.050
Mozilla/5.0 (X11; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.046

Country

fingerprintco-occurrences
NL · Netherlands730
US · United States558
AU · Australia366
DE · Germany254
GB · United Kingdom235
TR · Turkey97
CA · Canada94
FR · France48
CH · Switzerland46
RU · Russia23

Network (ASN)

fingerprintco-occurrences
AS218785 · TC DATACENTER LIMITED506
AS38195 · Superloop334
AS8468 · ENTANET International Limited194
AS132892 · Cloudflare, Inc.188
AS219502 · Storm Industries LLC163
AS212238 · Datacamp Limited109
AS205100 · F3 Netze e.V.107
AS202623 · Cloudflare Inc89
AS211619 · MAXKO d.o.o.51
AS204770 · UAB "Cherry Servers"48

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.171
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.60
0a0a,11ec,001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 156.0.8078.48, edge 155.0.4283.62, chrome 156.0.8078.47, +11 more.The fingerprint page shows the full measured match list. More on the catalog.45
001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, winhttp 10.0.20348.1, +2 more.The fingerprint page shows the full measured match list. More on the catalog.27
11ec,11eb,11ed,001d,0017,001e,0019,0018,0100,0101,0102,0103,0104 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.23
0a0a,001d,0017,001816
001d,0017,0018,0019,001e,0100,0101,0102,0103,0104 Match?Exact match in Thumbprint's published controlled catalog captures: java-httpclient 17.0.19, java-httpclient 11.0.31, java-urlconnection 17.0.19, +2 more.The fingerprint page shows the full measured match list. More on the catalog.14
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.12
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.12
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

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_653d80c3fe9d81
q13d0312h3_55b375c5d22e_178839b6cec126
q13d0413h3_9caa18292e23_23fce1e67d9813
q13d0315h3_55b375c5d22e_dc5437974b4712
q13d0313h3_55b375c5d22e_fc7519ff7bc25
q13d0315h3_55b375c5d22e_bb76f32061e35
q13d0314h3_55b375c5d22e_61e396c58b1f3
q13d0314h3_55b375c5d22e_1ecea7cb6ec13
q13d0315h3_55b375c5d22e_78345df32b3a3
q13d0307h3_55b375c5d22e_1cecd519fee81