TCP SYN (p0f)

4:45+19:0:1460:65535,12:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-30 01:51 · last seen 2026-09-11 22:02 · 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+19:0:1460:65535,12:mss,sok,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/149.0.0.0 Safari/537.36 Edg/149.0.0.0
Observed TTL	45+19 (observed + path distance → initial)
Claimed OS	Windows
Confidence	low — single sighting of an environmental signal

low

2026-06-30

4:45+19:0:1460:65535,12:mss,sok,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

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0 Safari/537.36
Observed TTL	45+19 (observed + path distance → initial)
Claimed OS	Windows
Confidence	low — single sighting of an environmental signal

low

2026-07-12

Last 7 days (1 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	`45+19`
Options length	`0`
MSS	`1460`
Window size	`65535`
Window scale	`12`
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
`t13d351300_bfa337485184_c266ffd845cb`	13
`t13d160900_1711a4c0508c_c06d14d7e8f6`	1
`t13d131100_f57a46bbacb6_ab7e3b40a677` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.5, go-net/http 1.26.4.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn050000_b223a0ebb0b5_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: python-requests 2.34.2, python-requests 2.33.1, python-requests 2.32.3.The fingerprint page shows the full measured match list. More on the catalog.	13
`ge11nr15engb_fb9994e70428_000000000000_000000000000`	1
`ge11nr040000_e1d2031bdfea_000000000000_000000000000`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`65535_2-4-8-1-3_1460_12`	15

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (compatible; MJ12bot/v2.0.5; http://mj12bot.com/)`	13
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36 Edg/149.0.0.0`	1
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0 Safari/537.36`	1

Country

fingerprint	co-occurrences
`FR` · France	13
`AU` · Australia	1
`CN` · China	1

Network (ASN)

fingerprint	co-occurrences
`AS16276` · OVH SAS	13
`AS9983` · Australian Bureau of Statistics.	1
`AS38365` · Beijing Baidu Netcom Science and Technology Co., Ltd.	1