TCP SYN (p0f)

4:57+7:0:1460:mss*44,13:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-10-27 04:11 · last seen 2026-10-27 04:11 · 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

IP version	`4`
Initial TTL	`57+7`
Options length	`0`
MSS	`1460`
Window size	`mss*44`
Window scale	`13`
Options layout	`mss,sok,ts,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
`t13d1314h1_f57a46bbacb6_fb48f8b98a29`	1
`t13i1313h1_f57a46bbacb6_fb48f8b98a29`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn050000_a1c329e38462_000000000000_000000000000`	2

TCP SYN (JA4T)

fingerprint	co-occurrences
`64240_2-4-8-1-3_1460_13`	2

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (compatible; research-scan/1.0)`	2

Country

fingerprint	co-occurrences
`US` · United States	2

Network (ASN)

fingerprint	co-occurrences
`AS31898` · Oracle Corporation	2

TLS supported groups

fingerprint	co-occurrences
`11ec,001d,0017,0018,0019` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 157.0.1, firefox-esr 153.5.1esr, firefox 158.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.	2