TCP SYN (p0f)

4:49+15:0:1460:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df,ecn:0

first seen 2026-06-23 17:02 · last seen 2026-10-28 16:43 · 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

4:49+15:0:1460:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df,ecn:0

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

User-Agent claims Windows

TCP SYN initial TTL 49+15 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
Observed TTL	49+15 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-01

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	`49+15`
Options length	`0`
MSS	`1460`
Window size	`65535`
Window scale	`6`
Options layout	`mss,nop,ws,nop,nop,ts,sok,eol+1`
Quirks	`df,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
`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.	6
`t13d1516h2_8daaf6152771_806a8c22fdea` Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 151.0.7922.137, chromium 151.0.7922.34, +28 more.The fingerprint page shows the full measured match list. More on the catalog.	4
`t13d1712h1_ab0a1bf427ad_8e6e362c5eac`	3
`t13d1712h1_ab0a1bf427ad_882d495ac381`	3
`t13d1714h1_5b57614c22b0_7baf387fc6ff`	3
`t13d1715h1_5b57614c22b0_e8ed158c4d85`	2
`t13d1516h2_8daaf6152771_d8a2da3f94cd` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`t13d4907h2_0d8feac7bc37_7395dae3b2f3` Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.	1
`t13d1714h1_5b57614c22b0_43ade6aba3df`	1
`t13d1516h2_8daaf6152771_cd486ad61c78`	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn06enus_22f00d37a95d_000000000000_000000000000`	5
`ge11nn050000_be0d0b335e46_000000000000_000000000000`	2
`ge20nn05enus_3f99bc624e90_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: urlsession 6.3.2, urlsession 6.3.3.The fingerprint page shows the full measured match list. More on the catalog.	2
`ge20nr13enus_477eefb733f8_000000000000_000000000000`	1
`ge20nr14enus_b627e55c4c56_000000000000_000000000000`	1
`ge11nn040000_e9f51a8d70f3_000000000000_000000000000`	1
`ge20nn020000_5594a17e7e7e_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`ge20nr12engb_54b4638ab28b_000000000000_000000000000`	1
`ge20nr12enus_54b4638ab28b_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 152.0.7977.83, chrome 151.0.7922.137, +58 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`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, +2 more.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`1:65536;2:0;4:6291456;6:262144\|15663105\|1:1:0:256\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +57 more.The fingerprint page shows the full measured match list. More on the catalog.	3
`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, +2 more.The fingerprint page shows the full measured match list. More on the catalog.	3
`2:0;4:2097152;3:100;9:1\|10485760\|0\|m,s,p,a`	3
`1:65536;2:0;4:6291456;6:262144\|15663105\|1:1:0:220\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 152.0.7977.83, +81 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`1:65536;2:0;4:131072;5:16384\|12517377\|3:0:0:22\|m,p,a,s` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 155.0.1, +31 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`3:100;4:10485760;2:0\|1048510465\|0\|m,s,a,p` Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0.The fingerprint page shows the full measured match list. More on the catalog.	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`65535_2-1-3-1-1-8-4-0-0_1460_6`	23

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36`	3
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.36`	3
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0 Safari/537.36 isitvibecoded/1.0`	3
`HackerNews/1566 CFNetwork/3860.600.12 Darwin/25.5.0`	2
`Mozilla/5.0 (compatible; SecurityScanner/1.0)`	2
`Mozilla/5.0 (iPad; CPU OS 27_0_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/155.0.8059.37 Mobile/15E148 Safari/604.1`	2
`Mozilla/5.0 (compatible; isitvibecoded/1.0; +https://is-it-vibecoded.vercel.app)`	2
`curl/8.7.1`	1
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36`	1
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:153.0) Gecko/20100101 Firefox/153.0`	1

Country

fingerprint	co-occurrences
`US` · United States	13
`IN` · India	5
`GB` · United Kingdom	3
`RS` · Serbia	3
`AU` · Australia	1
`JP` · Japan	1

Network (ASN)

fingerprint	co-occurrences
`AS22773` · Cox Communications Inc.	6
`AS55836` · Reliance Jio Infocomm Limited	5
`AS6128` · Cablevision Systems Corp.	3
`AS31042` · Yettel d.o.o.	3
`AS14593` · Space Exploration Technologies Corporation	2
`AS5089` · Virgin Media Limited	2
`AS20055` · Wholesail networks LLC	2
`AS7018` · AT&T Enterprises, LLC	1
`AS20001` · Charter Communications Inc	1
`AS2516` · KDDI CORPORATION	1

TLS supported groups

fingerprint	co-occurrences
`001d,0017,0018` Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, powershell 7.6.8, +1 more.The fingerprint page shows the full measured match list. More on the catalog.	5
`0a0a,11ec,001d,0017,0018,0019`	3
`11ec,001d,0017,001e,0018,0019,0100,0101` Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 24.22.1, python-httpx 0.28.1, python-requests 2.34.2, +2 more.The fingerprint page shows the full measured match list. More on the catalog.	1

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprint	linked observations
`q13d0311h3_55b375c5d22e_653d80c3fe9d`	2
`q13d0311h3_55b375c5d22e_f2a83c8e78ae`	2
`q13d0315h3_55b375c5d22e_dc5437974b47`	1

fingerprint	co-occurrences
`1:65536;2:0;4:6291456;6:262144\|15663105\|1:1:0:256\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +57 more.The fingerprint page shows the full measured match list. More on the catalog.	3
`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, +2 more.The fingerprint page shows the full measured match list. More on the catalog.	3
`2:0;4:2097152;3:100;9:1\|10485760\|0\|m,s,p,a`	3
`1:65536;2:0;4:6291456;6:262144\|15663105\|1:1:0:220\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 152.0.7977.83, +81 more.The fingerprint page shows the full measured match list. More on the catalog.	2
`1:65536;2:0;4:131072;5:16384\|12517377\|3:0:0:22\|m,p,a,s` Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 155.0.1, +31 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`3:100;4:10485760;2:0\|1048510465\|0\|m,s,a,p` Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0.The fingerprint page shows the full measured match list. More on the catalog.	1