TCP SYN (p0f)

4:50+14:0:1460:mss*20,4:mss,nop,nop,sok,nop,ws:df,id+:0

first seen 2026-08-06 01:46 · last seen 2026-09-19 00:50 · JSON

Inconsistencies

User-Agents observed with this fingerprint that contradict what it proves at the wire. all inconsistencies →

fingerprint User-Agent claims wire shows confidence seen first seen last seen

4:50+14:0:1460:mss*20,4:mss,nop,nop,sok,nop,ws:df,id+:0

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:151…

User-Agent claims Windows

TCP SYN initial TTL 50+14 indicates Unix-like

The initial TTL is set by the sending kernel (64 on Unix-like systems, 128 on Windows) and survives NAT. But VPNs, proxies and tunnels legitimately replace the sending stack, so this check never exceeds medium confidence.

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:151.0) Gecko/20100101 Firefox/151.0
Observed TTL	50+14 (observed + path distance → initial)
Claimed OS	Windows
Confidence	low — single sighting of an environmental signal

low

2026-09-19

Decomposed attributes

IP version	`4`
Initial TTL	`50+14`
Options length	`0`
MSS	`1460`
Window size	`mss*20`
Window scale	`4`
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
`t13d2013h2_a09f3c656075_7f0f34a4126d` Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.4, +2 more.The fingerprint page shows the full measured match list. More on the catalog.	4
`t13d1617h2_86a278354501_3cbfd9057e0d` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.3, +10 more.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge20nn08enus_1945e0741196_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.4.The fingerprint page shows the full measured match list. More on the catalog.	2
`ge20nr09enus_5ad46a65401a_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.6.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`ge20nn11enus_3901d4197baf_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 153.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`2:0;3:100;4:2097152;9:1\|10420225\|0\|m,s,a,p` Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.5, +3 more.The fingerprint page shows the full measured match list. More on the catalog.	4
`1:65536;2:0;4:131072;5:16384\|12517377\|3:0:0:42\|m,p,a,s` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 152.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`29200_2-1-1-4-1-3_1460_4`	5

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/26.5 Safari/605.1.15`	4
`Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:151.0) Gecko/20100101 Firefox/151.0`	1

Country

fingerprint	co-occurrences
`US` · United States	5

Network (ASN)

fingerprint	co-occurrences
`AS701` · Verizon Business	5