TCP SYN (p0f)

6:49+15:0:1440:65535,8:mss,sok,ts,nop,ws:flow:0

first seen 2026-07-01 15:45 · last seen 2026-09-15 00:33 · 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

IP version	`6`
Initial TTL	`49+15`
Options length	`0`
MSS	`1440`
Window size	`65535`
Window scale	`8`
Options layout	`mss,sok,ts,nop,ws`
Quirks	`flow`
Payload class	`0`

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
`t13d1515h1_8daaf6152771_0a20fe35d3a5`	2
`t13d1517h2_8daaf6152771_3cbfd9057e0d` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 154.0.1, firefox 155.0.1, +1 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`t13d1515h2_8daaf6152771_e8ed158c4d85`	1
`t13d2013h1_2b729b4bf6f3_e24568c0d440`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge20nr10enus_b3034183f430_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 154.0, +21 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`ge20nn030000_80b089f68b8e_000000000000_000000000000`	1
`ge11nn13enus_9db22d02e17a_000000000000_000000000000`	1
`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
`ge11nn14enus_4a2973d235de_000000000000_000000000000`	1

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`1:4096;2:0;4:32768;5:16384\|12517377\|3:0:0:22\|m,p,a,s`	2
`4:16777216\|16711681\|0\|m,p,a,s`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`65535_2-4-8-1-3_1440_8`	6

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Android 17; Mobile; rv:155.0) Gecko/155.0 Firefox/155.0`	2
`Harmonic-HN-Android/3.0.1/release`	1
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36`	1
`curl/8.21.0`	1
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36`	1

Country

fingerprint	co-occurrences
`US` · United States	5
`GB` · United Kingdom	1

Network (ASN)

fingerprint	co-occurrences
`AS7922` · Comcast Cable Communications, LLC	5
`AS5607` · Sky UK Limited	1

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprint	linked observations
`q13d0315h3_55b375c5d22e_dc5437974b47`	2