TCP SYN (JA4T)

43200_2-4-8-1-3_1440_11

first seen 2026-07-03 16:54 · last seen 2026-09-15 15:58 · 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 window43200
Option kinds2-4-8-1-3
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_a54fffd0eb616
t13d2614h2_2802a3db6c62_a5b99884f7f56
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.5
t13d3013h1_1d37bd780c83_ecd0401ec68b4
t13d4907h2_0d8feac7bc37_7395dae3b2f3 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.2
t13d3013h2_1d37bd780c83_8537cf56674e2
t13d1312h2_f57a46bbacb6_ab7e3b40a677 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, +5 more.The fingerprint page shows the full measured match list. More on the catalog.2
t13d301100_1d37bd780c83_8e6e362c5eac2
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.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr010000_c125d0397b60_000000000000_0000000000006
ge20nr11enus_187a9385d229_000000000000_0000000000005
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
ge20nn04enus_ded3c6d8f0eb_000000000000_0000000000004
ge11nr030000_cd680697de12_000000000000_0000000000003
ge11nr09enus_584cf71d8dfa_000000000000_0000000000002
ge20nr020000_fb4f949fd323_000000000000_0000000000002
ge11nn030000_47c2bbddfa85_000000000000_0000000000002
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.1
ge20nn12enus_a72b71f519fc_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
4:2097152;3:100|10485760|0|m,s,p,a6
1:4096;2:0;4:65535;5:16384;3:100;6:65536|16777216|0|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1.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 154.0, +25 more.The fingerprint page shows the full measured match list. More on the catalog.3
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.2
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.2
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.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.1
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.1
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

TCP SYN (p0f)

fingerprintco-occurrences
6:43+21:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:08
6:50+14:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:07
6:41+23:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:06
6:52+12:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:03
6:48+16:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:02
6:51+13:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:02
6:42+22:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:01
6:59+5:0:1440:mss*30,11:mss,sok,ts,nop,ws:flow:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.05
Go-http-client/1.13
Mozilla/5.02
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.02
curl/8.7.12
curl/8.14.12
codex-tui/0.154.0 (Ubuntu 22.4.0; x86_64) xterm-256color2
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.01
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.361

Country

fingerprintco-occurrences
DE · Germany14
US · United States7
SG · Singapore7
AT · Austria2

Network (ASN)

fingerprintco-occurrences
AS197540 · netcup GmbH13
AS38136 · Akari Networks7
AS14061 · DigitalOcean, LLC4
AS917 · Misaka Network, Inc.3
AS47147 · ANEXIA Internetdienstleistungs GmbH2
AS60729 · Stiftung Erneuerbare Freiheit1