TCP SYN (p0f)

6:51+13:0:1440:8192,8:mss,nop,ws,nop,nop,sok:ecn:0

first seen 2026-09-22 10:14 · last seen 2026-09-28 16:06 · 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

6:51+13:0:1440:8192,8:mss,nop,ws,nop,nop,sok:ecn:0

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

User-Agent claims Windows

TCP SYN initial TTL 51+13 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/126.0.0.0 Safari/537.36
Observed TTL	51+13 (observed + path distance → initial)
Claimed OS	Windows
Confidence	low — single sighting of an environmental signal

low

2026-09-22

2026-09-28

Decomposed attributes

IP version	`6`
Initial TTL	`51+13`
Options length	`0`
MSS	`1440`
Window size	`8192`
Window scale	`8`
Options layout	`mss,nop,ws,nop,nop,sok`
Quirks	`ecn`
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
`t12d4907h1_730fb1b0ac6a_8587f467d9ea`	2

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn050000_0b4164a3b800_000000000000_000000000000`	2

TCP SYN (JA4T)

fingerprint	co-occurrences
`8192_2-1-3-1-1-4_1440_8`	2

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36`	2

Country

fingerprint	co-occurrences
`SG` · Singapore	2

Network (ASN)

fingerprint	co-occurrences
`AS63949` · Akamai Connected Cloud	2