TCP SYN (JA4T)

42340_2-4-8-1-3_1452_9

first seen 2026-07-01 15:18 · last seen 2026-10-18 18:29 · JSON

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 window42340
Option kinds2-4-8-1-3
MSS1452
Window scale9

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_b26ce05bbdd62
t13d3013h2_1d37bd780c83_8537cf56674e 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.2
t13d1713h1_ab0a1bf427ad_8537cf56674e Match?Exact match in Thumbprint's published controlled catalog captures: python-requests 2.34.2, python-requests 2.32.3, python-requests 2.33.1.The fingerprint page shows the full measured match list. More on the catalog.1
t13d521100_b262b3658495_8e6e362c5eac1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.2
ge11nn07enus_71b742b5154a_000000000000_0000000000001
ge11nn06enus_fb4afd1f380a_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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, +8 more.The fingerprint page shows the full measured match list. More on the catalog.2

TCP SYN (p0f)

fingerprintco-occurrences
4:47+17:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01
4:51+13:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01
4:52+12:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01
4:45+19:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01
4:40+24:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01
4:48+16:0:1452:mss*29,9:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
curl/8.14.12
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.361
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/136.0.0.0 Safari/537.361
Mozilla/5.0 (compatible; The Lounge IRC Client; +https://github.com/thelounge/thelounge) facebookexternalhit/1.1 Twitterbot/1.01

Country

fingerprintco-occurrences
MA · Morocco2
AU · Australia1
CA · Canada1
ES · Spain1
VE · Venezuela1

Network (ASN)

fingerprintco-occurrences
AS36903 · Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM2
AS1403 · EBOX1
AS7545 · TPG Telecom Limited1
AS57269 · DIGI SPAIN TELECOM S.A1
AS269730 · TECNOVEN SERVICES CA1

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.2