TCP SYN (JA4T)

42340_2-4-8-1-3_1452_7

first seen 2026-07-24 15:41 · last seen 2026-10-02 08:41 · 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 window	`42340`
Option kinds	`2-4-8-1-3`
MSS	`1452`
Window scale	`7`

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)

fingerprint	co-occurrences
`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.	6
`t13d4412h1_fd39b124ee10_58ed7828516f`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`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.	6
`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.	1

HTTP/2 frames (Akamai)

fingerprint	co-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

TCP SYN (p0f)

fingerprint	co-occurrences
`4:47+17:0:1452:mss*29,7:mss,sok,ts,nop,ws:df,id+:0`	3
`4:49+15:0:1452:mss*29,7:mss,sok,ts,nop,ws:df,id+:0`	2
`4:50+14:0:1452:mss*29,7:mss,sok,ts,nop,ws:df,id+:0`	1
`4:48+16:0:1452:mss*29,7:mss,sok,ts,nop,ws:df,id+:0`	1

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36`	6
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_1) AppleWebKit/537.36 (KHTML, like Gecko) Brave Chrome/78.0.3904.70 Safari/537.36`	1

Country

fingerprint	co-occurrences
`CN` · China	6
`PK` · Pakistan	1

Network (ASN)

fingerprint	co-occurrences
`AS24445` · Henan Mobile Communications Co.,Ltd	2
`AS56048` · China Mobile Communicaitons Corporation	2
`AS4134` · CHINANET BACKBONE	1
`AS4837` · CHINA UNICOM China169 Backbone	1
`AS150683` · FASTTEL BROADBAND (PRIVATE) LIMITED	1