TCP SYN (p0f)

4:45+19:0:1340:64390,10:mss,nop,nop,sok,nop,ws:df,id+:0

first seen 2026-08-23 21:06 · last seen 2026-08-23 21:06 · 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

IP version	`4`
Initial TTL	`45+19`
Options length	`0`
MSS	`1340`
Window size	`64390`
Window scale	`10`
Options layout	`mss,nop,nop,sok,nop,ws`
Quirks	`df,id+`
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
`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, +24 more.The fingerprint page shows the full measured match list. More on the catalog.	5

HTTP request (JA4H)

fingerprint	co-occurrences
`ge20nr12enus_c80363b31072_000000000000_000000000000`	4
`ge20nn12enus_f3273f86d6bc_000000000000_000000000000`	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, +43 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|7:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|9:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|11:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|13:1:0:256\|m,a,s,p`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`64390_2-1-1-4-1-3_1340_10`	5

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.0.0 Safari/537.36`	5

Country

fingerprint	co-occurrences
`FI` · Finland	5

Network (ASN)

fingerprint	co-occurrences
`AS39351` · 31173 Services AB	5

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, +43 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|7:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|9:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|11:1:0:256\|m,a,s,p`	1
`1:65536;2:0;4:6291456;6:262144\|15663105\|13:1:0:256\|m,a,s,p`	1