TCP SYN (p0f)

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

first seen 2026-06-25 11:36 · last seen 2026-09-16 11:46 · 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

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

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 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.186 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

115

2026-07-29

2026-08-17

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) …

User-Agent claims macOS

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36 Chrome-Lighthouse
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	macOS
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-25

2026-09-13

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.128 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-20

2026-07-29

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 11; moto g power (20…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 11; moto g power (2022)) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Mobile Safari/537.36 Chrome-Lighthouse
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-06-25

2026-09-13

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.7922.173 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-08-26

2026-09-09

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.7922.137 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-08-18

2026-08-25

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.84 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-01

2026-09-13

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.46 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-04

2026-07-15

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/5…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Mobile Safari/537.36 (compatible; Google-Read-Aloud; +https://support.google.com/webmasters/answer/1061943)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-28

2026-09-08

4:121+7:0:1412:65535,8:mss,sok,ts,nop,ws::0

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Buil…

User-Agent claims Android

TCP SYN initial TTL 121+7 indicates Windows

Full User-Agent	Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.124 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Observed TTL	121+7 (observed + path distance → initial)
Claimed OS	Android
Confidence	medium — repeated co-occurrence, but initial TTL is environmental — capped at medium

medium

2026-07-17

2026-07-20

Last 7 days (50 observations)

Distinct clients per day (last 30 days, peak 18/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	`121+7`
Options length	`0`
MSS	`1412`
Window size	`65535`
Window scale	`8`
Options layout	`mss,sok,ts,nop,ws`
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
`t13d181300_e8a523a41297_43ade6aba3df`	994
`t13d1712h2_5b57614c22b0_ef7df7f74e48`	186

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn050000_c727097c2f59_000000000000_000000000000`	435
`ge11nn080000_6b4f92f3c7df_000000000000_000000000000`	232
`ge11nn070000_5583da70a3c4_000000000000_000000000000`	154
`ge11nn060000_1726a8486418_000000000000_000000000000`	79
`ge20nr080000_eac7452ad7da_000000000000_000000000000`	75
`ge20nn070000_fad2baeaef05_000000000000_000000000000`	40
`ge11nn060000_a664e4fabf5b_000000000000_000000000000`	30
`ge20nr070000_fad2baeaef05_000000000000_000000000000`	21
`ge11nn040000_51be388b7c20_000000000000_000000000000`	16
`ge20nr090000_65d4d215624f_000000000000_000000000000`	13

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`2:0;1:4096;8:0;3:1024;4:33554432\|25100289\|0\|m,s,p,a`	186

TCP SYN (JA4T)

fingerprint	co-occurrences
`65535_2-4-8-1-3_1412_8`	1129

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	450
`Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.186 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	115
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.36 Chrome-Lighthouse`	95
`Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.7871.128 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	92
`Mozilla/5.0 (Linux; Android 11; moto g power (2022)) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Mobile Safari/537.36 Chrome-Lighthouse`	91
`Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.7922.173 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	78
`Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/151.0.7922.137 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	41
`Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.84 Mobile Safari/537.36 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)`	35
`Chrome Privacy Preserving Prefetch Proxy`	31
`Google-Lens`	28

Country

fingerprint	co-occurrences
`US` · United States	1066
`TW` · Taiwan	34
`NL` · Netherlands	29
`BE` · Belgium	24
`FI` · Finland	16
`SG` · Singapore	9
`IE` · Ireland	2

Network (ASN)

fingerprint	co-occurrences
`AS15169` · Google LLC	1161
`AS396982` · Google LLC	19