TCP SYN (p0f)

4:56+8:0:1460:mss*29,11:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-25 18:55 · last seen 2026-09-10 11:37 · JSON

Inconsistencies

User-Agents observed with this fingerprint that contradict what it proves at the wire. Showing the first 10 here. all inconsistencies →

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

4:56+8:0:1460:mss*29,11: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 56+8 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/120.0.0.0 Safari/537.36
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-08-25

2026-09-10

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

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	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-08-14

4:56+8:0:1460:mss*29,11:mss,sok,ts,nop,ws:df,id+:0

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:127…

User-Agent claims Windows

TCP SYN initial TTL 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:127.0) Gecko/20100101 Firefox/127.0
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36 Vivaldi/6.7.3329.35
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36 Edg/125.0.0.0
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11:mss,sok,ts,nop,ws:df,id+:0

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:126…

User-Agent claims Windows

TCP SYN initial TTL 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:126.0) Gecko/20100101 Firefox/126.0
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

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 Edg/126.0.0.0
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

4:56+8:0:1460:mss*29,11: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 56+8 indicates Unix-like

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36 OPR/110.0.0.0
Observed TTL	56+8 (observed + path distance → initial)
Claimed OS	Windows
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-30

2026-07-16

Last 7 days (9 observations)

Distinct clients per day (last 30 days, peak 3/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	`56+8`
Options length	`0`
MSS	`1460`
Window size	`mss*29`
Window scale	`11`
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
`t13d151100_8daaf6152771_ab7e3b40a677`	812
`t13d1312h1_f57a46bbacb6_ab7e3b40a677`	74
`t13d141100_cbb2034c60b8_e5728521abd4`	14
`t13d141000_cbb2034c60b8_e7c285222651` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.22.12.The fingerprint page shows the full measured match list. More on the catalog.	13
`t13d181100_85036bcba153_d41ae481755e`	10
`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.	9
`t13d1312h2_f57a46bbacb6_ab7e3b40a677` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.8, go-net/http 1.26.7, +5 more.The fingerprint page shows the full measured match list. More on the catalog.	6
`t13d191100_9dc949149365_e5728521abd4`	4
`t13d1912h2_9dc949149365_e5728521abd4`	2
`t13d191000_9dc949149365_e7c285222651`	2

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nr38enus_423680453bc1_000000000000_000000000000`	29
`ge11nr37enus_49f6cf8b676e_000000000000_000000000000`	28
`ge11nr37enus_4fc02c8dab26_000000000000_000000000000`	28
`ge11nr39enus_8275968c859c_000000000000_000000000000`	23
`ge11nr39enus_1c19b8b5959c_000000000000_000000000000`	21
`ge11nr38enus_c9f28418db6b_000000000000_000000000000`	21
`ge11nr040000_e1d2031bdfea_000000000000_000000000000`	17
`ge11nr41enus_c0fe3e80018a_000000000000_000000000000`	15
`ge11nr05enus_900748f1e0f3_000000000000_000000000000`	15
`ge11nr34enus_ee7234eb47b7_000000000000_000000000000`	11

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`2:0;4:4194304;5:16384;6:10485760\|1073741824\|0\|a,m,p,s` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.8, go-net/http 1.26.7, +6 more.The fingerprint page shows the full measured match list. More on the catalog.	8

TCP SYN (JA4T)

fingerprint	co-occurrences
`42340_2-4-8-1-3_1460_11`	943

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36`	49
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36`	48
`Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.15`	44
`Mozilla/5.0 (Macintosh; Intel Mac OS X 14_4_1) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.4.1 Safari/605.1.15`	39
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36`	38
`Mozilla/5.0 (Linux; Android 14; Pixel 8 Pro) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Mobile Safari/537.36`	38
`Mozilla/5.0 (X11; Linux x86_64; rv:127.0) Gecko/20100101 Firefox/127.0`	38
`Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36`	37
`Mozilla/5.0 (iPhone; CPU iPhone OS 17_5_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Mobile/15E148 Safari/604.1`	36
`Mozilla/5.0 (Linux; U; Android 14; en-US; Redmi Note 13 Pro Build/UP1A.231005.007) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 UCBrowser/13.4.0.1306 Mobile Safari/537.36`	36

Country

fingerprint	co-occurrences
`NL` · Netherlands	940
`AD` · Andorra	6

Network (ASN)

fingerprint	co-occurrences
`AS48090` · TECHOFF SRV LIMITED	944
`AS197170` · TechTies Inc.	2