TCP SYN (JA4T)

65535_2-1-3-4-8_1452_8

first seen 2026-07-18 08:25 · last seen 2026-08-31 06:56 · JSON

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 window65535
Option kinds2-1-3-4-8
MSS1452
Window scale8

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
t13d2013h1_2b729b4bf6f3_e24568c0d44011
t13d181100_85036bcba153_d41ae481755e10
t13d2913h1_723694b0fccc_5671b5df50299
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.5
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.5
t12d1515h2_8daaf6152771_4d8a99c1bc011
t13d171000_5b57614c22b0_78e6aca7449b1
t13d201100_2b729b4bf6f3_36bf25f296df1

HTTP request (JA4H)

fingerprintco-occurrences
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.11
ge11nn040000_08e7224bf8c7_000000000000_0000000000009
ge11nr11ruru_835281d8e5d9_000000000000_0000000000005
ge20nr13ruru_9e2b86631664_000000000000_0000000000004
ge20nr16ruru_94fdc06e0694_000000000000_0000000000004
ge20nr16thth_94fdc06e0694_000000000000_0000000000001
ge20nr09zhcn_4886f2cdeb15_000000000000_0000000000001
ge11nn050000_2469c960a647_000000000000_0000000000001
ge11nn030000_b0d6a43aa599_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: powershell 5.1.26100.33296, powershell 5.1.26100.33158, powershell 5.1.26100.32995.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn030000_69803879d94f_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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.5
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;3:1000;4:6291456;5:16384;6:262144|15663105|0|m,a,s,p1

TCP SYN (p0f)

fingerprintco-occurrences
4:118+10:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+:010
4:47+17:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+,ecn:07
4:46+18:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+,ecn:06
4:43+21:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+,ecn:03
4:50+14:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+,ecn:03
4:44+20:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+,ecn:02
4:110+18:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+:02
4:117+11:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+:02
4:108+20:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+:01
4:114+14:0:1452:65535,8:mss,nop,ws,sok,ts:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.09
curl/8.18.08
Mozilla/5.0 (iPhone; CPU iPhone OS 17_6 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.6 Mobile/15E148 Safari/604.14
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.03
Mozilla/5.0 (X11; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.03
Mozilla/5.0 (iPhone; CPU iPhone OS 17_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.2 Mobile/15E148 Safari/604.12
Mozilla/5.0 (Android 14; Mobile; rv:153.0) Gecko/153.0 Firefox/153.02
Mozilla/5.0 (Linux; Android 14; Pixel 9 Pro) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Mobile Safari/537.362
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.361
Mozilla/5.0 (iPhone; CPU iPhone OS 18_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1 Mobile/15E148 Safari/604.11

Country

fingerprintco-occurrences
VN · Vietnam23
RU · Russia16
BE · Belgium2
TH · Thailand1
CN · China1

Network (ASN)

fingerprintco-occurrences
AS12389 · PJSC Rostelecom16
AS7552 · Viettel Group10
AS18403 · FPT Telecom Company8
AS45899 · VNPT Corp5
AS5432 · Proximus NV2
AS4134 · CHINANET BACKBONE1
AS133481 · AIS Fibre1