TCP SYN (p0f)

4:45+19:0:1460:65535,9:mss,nop,nop,ts,nop,ws:df,id+:0

first seen 2026-07-31 21:09 · last seen 2026-07-31 21:09 · 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

4:45+19:0:1460:65535,9:mss,nop,nop,ts,nop,ws:df,id+:0

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleW…

User-Agent claims Windows

TCP SYN initial TTL 45+19 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) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36
Observed TTL	45+19 (observed + path distance → initial)
Claimed OS	Windows
Confidence	low — single sighting of an environmental signal

low

2026-07-31

Decomposed attributes

IP version	`4`
Initial TTL	`45+19`
Options length	`0`
MSS	`1460`
Window size	`65535`
Window scale	`9`
Options layout	`mss,nop,nop,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
`t13d141100_cbb2034c60b8_e5728521abd4`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`he11nn030000_fe444ad14866_000000000000_000000000000`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`65535_2-1-1-8-1-3_1460_9`	1

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36`	1

Country

fingerprint	co-occurrences
`CH` · Switzerland	1

Network (ASN)

fingerprint	co-occurrences
`AS51852` · Private Layer INC	1