TCP SYN (JA4T)

64240_2-4-8-1-3_1452_10

first seen 2026-07-01 17:27 · last seen 2026-09-13 04:35 · JSON

Last 7 days (2 observations)

Distinct clients per day (last 30 days, peak 1/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
MSS1452
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
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.18
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.5
t13d1616h2_86a278354501_0c27189014cf Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.6, +10 more.The fingerprint page shows the full measured match list. More on the catalog.4
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.4
t13d3112h2_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.5.0, php-curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.3
t13d521100_b262b3658495_8e6e362c5eac2
t13d1411h2_cbb2034c60b8_e7c2852226512
t13d3113h1_e8f1e7e78f70_d339722ba4af2
t13d301100_1d37bd780c83_8e6e362c5eac2
t13d3513h2_bfa337485184_8d7351bd871b 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.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr10enus_b3034183f430_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 154.0, +21 more.The fingerprint page shows the full measured match list. More on the catalog.15
ge20nn11enus_3901d4197baf_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 153.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.5
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.4
ge20nr12enus_f8a3a1e39dc3_000000000000_0000000000003
ge20nn13enus_9e2b86631664_000000000000_0000000000002
ge20nn13en00_30dc68305204_000000000000_0000000000002
ge20nn14en00_1ea4ae3ab00a_000000000000_0000000000002
ge11nn050000_f42f60d0fe7d_000000000000_0000000000002
ge20nr020000_fb4f949fd323_000000000000_0000000000001
ge11nn06enus_ff871664fb50_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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.11
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.6
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.3
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.3
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.3
2:0;4:4194304;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.2
1:65536;2:0;4:131072;5:16384|12517377|7:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0.3, firefox 155.0, firefox 154.0, +3 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.1
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.1

TCP SYN (p0f)

fingerprintco-occurrences
4:50+14:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:012
4:51+13:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:010
4:47+17:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:09
4:44+20:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:04
4:53+11:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:04
4:45+19:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:02
4:46+18:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:02
4:48+16:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:02
4:41+23:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:01
4:52+12:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.018
Mozilla/5.0 (X11; Linux x86_64; rv:151.0) Gecko/20100101 Firefox/151.05
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.364
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.364
curl/8.5.03
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.02
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.362
fingerprint-security-thumbprint-probe/1.02
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.361

Country

fingerprintco-occurrences
VN · Vietnam26
ES · Spain8
IT · Italy6
US · United States4
MA · Morocco2
ZA · South Africa1

Network (ASN)

fingerprintco-occurrences
AS18403 · FPT Telecom Company24
AS3352 · TELEFONICA DE ESPANA S.A.U.6
AS3269 · Telecom Italia S.p.A.6
AS22302 · INOC, LLC4
AS36903 · Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM2
AS7552 · Viettel Group2
AS6739 · Vodafone ONO AS2
AS20011 · Dimension Data1

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
q13d0315h3_55b375c5d22e_dc5437974b475
q13d0311h3_55b375c5d22e_653d80c3fe9d4
q13d0314h3_55b375c5d22e_61e396c58b1f2