TCP SYN (JA4T)

64240_2-4-8-1-3_1340_7

first seen 2026-06-30 23:04 · last seen 2026-10-30 18:47 · JSON

Last 7 days (6 observations)

Distinct clients per day (last 30 days, peak 4/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
MSS1340
Window scale7

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
t13d4312h1_c7886603b240_b26ce05bbdd623
t13d3112h1_e8f1e7e78f70_d41ae481755e10
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.8
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
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.4
t13d1717h2_5b57614c22b0_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 148.0.2, firefox 144.0.2, firefox 142.0.1, +6 more.The fingerprint page shows the full measured match list. More on the catalog.3
t13d1516h2_8daaf6152771_02713d6af862 Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 134.0.6998.35, chromium 133.0.6943.16.The fingerprint page shows the full measured match list. More on the catalog.2
t13d311000_e8f1e7e78f70_1f22a2ca17c42
t13d1515h1_8daaf6152771_0a20fe35d3a51
t13d2013h1_2b729b4bf6f3_e24568c0d4401

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.23
ge11nn050000_be0d0b335e46_000000000000_00000000000010
ge20nr14enus_6a9d1f4fafe3_000000000000_0000000000004
ge20nr110000_65ce3e7a57b3_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chromium 151.0.7922.34, chromium 153.0.8010.12, chromium 156.0.8078.4, +13 more.The fingerprint page shows the full measured match list. More on the catalog.3
ge11nr030000_cd680697de12_000000000000_0000000000002
ge11nn030000_cd680697de12_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: powershell 7.6.6, powershell 7.6.5, powershell 7.6.4, +11 more.The fingerprint page shows the full measured match list. More on the catalog.2
ge20nn13enus_0c2c1d640f3e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 151.0.7922.137, chrome 151.0.7922.170, chrome 151.0.7922.108, +36 more.The fingerprint page shows the full measured match list. More on the catalog.2
ge11nn13enus_9db22d02e17a_000000000000_0000000000002
ge11nn050000_65fd75e05a8c_000000000000_0000000000002
ge20nr10pagb_b3034183f430_000000000000_0000000000002

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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, +57 more.The fingerprint page shows the full measured match list. More on the catalog.6
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:220|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, +81 more.The fingerprint page shows the full measured match list. More on the catalog.4
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, +31 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.2
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.1
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.1
1:65536;2:0;4:6291456;6:262144|15663105|3:1:0:256|m,a,s,p1

TCP SYN (p0f)

fingerprintco-occurrences
4:43+21:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:012
4:45+19:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:08
4:54+10:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:06
4:46+18:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:06
4:47+17:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:05
4:53+11:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:05
4:56+8:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:05
4:44+20:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:03
4:42+22:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:03
4:51+13:0:1340:mss*44,7:mss,sok,ts,nop,ws:df,id+:02

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.367
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.365
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.365
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.364
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.364
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.0 Safari/605.1.154
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12.2464
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.363
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:135.0) Gecko/20100101 Firefox/135.03
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.362

Country

fingerprintco-occurrences
IT · Italy25
US · United States11
GB · United Kingdom11
CA · Canada6
CH · Switzerland4
ES · Spain1
PR · Puerto Rico1

Network (ASN)

fingerprintco-occurrences
AS1267 · WIND TRE S.P.A.20
AS201738 · UFO TECHNOLOGIES LIMITED10
AS212238 · Datacamp Limited9
AS11878 · tzulo, inc.7
AS39351 · 31173 Services AB4
AS24608 · WIND TRE S.P.A.4
AS12874 · Fastweb SpA1
AS206067 · Hutchison 3G UK Limited1
AS200845 · AVATEL TELECOM, SA1
AS14638 · Liberty Communications of Puerto Rico LLC1

TLS supported groups

fingerprintco-occurrences
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.16
0a0a,11ec,001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 155.0.8059.40, chrome 156.0.8078.73, chromium 156.0.8078.47, +8 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.2

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
q13d0314h3_55b375c5d22e_61e396c58b1f2