TCP SYN (JA4T)

43200_2-1-1-4-1-3_1440_11

first seen 2026-07-06 10:41 · last seen 2026-10-30 10:55 · JSON

Last 7 days (3 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 window43200
Option kinds2-1-1-4-1-3
MSS1440
Window scale11

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
t13d1715h2_5b57614c22b0_a54fffd0eb6116
t12d290700_fc2078a0b8c0_8c06664c3ac513
t13d1714h2_5b57614c22b0_3dd24b5ebec45

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr12enus_a72b71f519fc_000000000000_0000000000008
ge11nn06en00_3011d71998e2_000000000000_0000000000008
ge20nr11enus_187a9385d229_000000000000_0000000000007
ge20nn12enus_a72b71f519fc_000000000000_0000000000005
ge11nn040000_bfa5a9b89dd6_000000000000_0000000000005
ge20nr11enus_684b26f0fcdf_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 155.0.1, +31 more.The fingerprint page shows the full measured match list. More on the catalog.3
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.2
1:4096;2:0;4:32768;5:16384|12517377|3:0:0:22|m,p,a,s2
1:4096;2:0;4:32768;5:16384|12517377|3:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|17:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|11:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|13:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|15:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|19:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|21:0:0:42|m,p,a,s1

TCP SYN (p0f)

fingerprintco-occurrences
6:59+5:0:1440:mss*30,11:mss,nop,nop,sok,nop,ws:flow:021
6:42+22:0:1440:mss*30,11:mss,nop,nop,sok,nop,ws:flow:09
6:43+21:0:1440:mss*30,11:mss,nop,nop,sok,nop,ws:flow:04

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.016
Mozilla/5.0 (compatible; MJ12bot/v1.4.8; http://mj12bot.com/)13
Mozilla/5.0 (Android 10; Mobile; rv:140.0) Gecko/140.0 Firefox/140.05

Country

fingerprintco-occurrences
DE · Germany34

Network (ASN)

fingerprintco-occurrences
AS60729 · Stiftung Erneuerbare Freiheit21
AS197540 · netcup GmbH13

TLS supported groups

fingerprintco-occurrences
001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, powershell 7.6.8, +1 more.The fingerprint page shows the full measured match list. More on the catalog.3