TCP SYN (JA4T)

64240_2-4-8-1-3_1460_10

first seen 2026-06-29 22:24 · last seen 2026-09-16 12:12 · JSON

Last 7 days (145 observations)

Distinct clients per day (last 30 days, peak 20/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
t13d1712h1_ab0a1bf427ad_8e6e362c5eac200
t13d101000_61a7ad8aa9b6_3ea2f44fd1af116
t13d4113h2_8ae0994cad11_86f67be995ff108
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.98
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.94
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
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.68
t13d1615h2_86a278354501_a54fffd0eb6163
t13d3112h1_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: php-guzzle 8.1.0, php-guzzle 8.0.2, php-guzzle 7.14.2, +6 more.The fingerprint page shows the full measured match list. More on the catalog.34
t13d131000_f57a46bbacb6_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.28

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn10engb_ec5486a7d5a7_000000000000_000000000000185
ge11nn050000_fdb72fc7d4c1_000000000000_000000000000116
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.104
ge20nn04enus_989c7cc05c9b_000000000000_00000000000081
ge11nr06enus_aeac3047b50b_000000000000_00000000000077
ge20nr12enus_a72b71f519fc_000000000000_00000000000065
ge20nr12engb_54b4638ab28b_000000000000_00000000000064
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.41
ge20nr11enus_187a9385d229_000000000000_00000000000038
ge11nn13enus_9db22d02e17a_000000000000_00000000000033

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, +7 more.The fingerprint page shows the full measured match list. More on the catalog.118
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.96
1:65536;2:0;4:6291456;6:262144;4:1048576|15663105|1:0:0:256|m,a,s,p81
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 154.0, +25 more.The fingerprint page shows the full measured match list. More on the catalog.55
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.46
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.33
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, +21 more.The fingerprint page shows the full measured match list. More on the catalog.18
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.15
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 1.26.8, go-net/http 1.26.7, +6 more.The fingerprint page shows the full measured match list. More on the catalog.15
1:65536;2:0;4:131072;5:16384|12517377|5:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0.3, firefox 154.0, firefox 153.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.12

TCP SYN (p0f)

fingerprintco-occurrences
4:55+9:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0234
4:43+21:0:1460:mss*44,10:mss,sok,ts,nop,ws::0190
4:50+14:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0149
4:54+10:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0131
4:47+17:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0118
4:51+13:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:077
4:56+8:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:055
4:53+11:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:052
4:48+16:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:051
4:45+19:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:045

User-Agent

fingerprintco-occurrences
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/537.36116
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36101
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.3695
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
curl/8.5.047
Mozilla/5.0 (X11; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.046
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.040
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.3631

Country

fingerprintco-occurrences
AU · Australia290
GB · United Kingdom197
US · United States188
NL · Netherlands160
DE · Germany99
TR · Turkey91
CA · Canada80
CH · Switzerland34
FR · France25
IE · Ireland19

Network (ASN)

fingerprintco-occurrences
AS38195 · Superloop265
AS8468 · ENTANET International Limited194
AS219502 · Storm Industries LLC114
AS218785 · TC DATACENTER LIMITED95
AS205100 · F3 Netze e.V.78
AS11351 · Charter Communications Inc44
AS5645 · TekSavvy Solutions, Inc.39
AS204770 · UAB Cherry Servers36
AS209854 · Cyberzone S.A.32
AS13030 · Init7 (Switzerland) Ltd.26

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_653d80c3fe9d76
q13d0413h3_9caa18292e23_23fce1e67d9813
q13d0315h3_55b375c5d22e_dc5437974b4712
q13d0315h3_55b375c5d22e_bb76f32061e35
q13d0313h3_55b375c5d22e_fc7519ff7bc24
q13d0312h3_55b375c5d22e_178839b6cec13
q13d0314h3_55b375c5d22e_61e396c58b1f3
q13d0314h3_55b375c5d22e_1ecea7cb6ec13
q13d0307h3_55b375c5d22e_1cecd519fee81
q13d0313h3_55b375c5d22e_eb028bd37c081