TCP SYN (p0f)

4:46+18:0:1460:mss*20,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-12 03:53 · last seen 2026-09-15 03:03 · JSON

Last 7 days (2 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 version4
Initial TTL46+18
Options length0
MSS1460
Window sizemss*20
Window scale7
Options layoutmss,sok,ts,nop,ws
Quirksdf,id+
Payload class0

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)

fingerprintco-occurrences
t13d191000_9dc949149365_e7c28522265115
t12d990700_a40d17a72bcb_4446390ac2244
t13d191100_9dc949149365_e5728521abd42
t13d521100_b262b3658495_8e6e362c5eac2
t13d3112h2_e8f1e7e78f70_8d633dac71242
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.2
t13i1712h1_ab0a1bf427ad_ecd0401ec68b1
t13d1515h1_8daaf6152771_0a20fe35d3a51
t13i170900_5b57614c22b0_78e6aca7449b1
t13d4312h1_c7886603b240_b26ce05bbdd61

HTTP request (JA4H)

fingerprintco-occurrences
ge11nr040000_e1d2031bdfea_000000000000_00000000000015
ge11nn040000_08e7224bf8c7_000000000000_0000000000004
ge11nr030000_0db47b7d240d_000000000000_0000000000002
ge11nn07enus_71b742b5154a_000000000000_0000000000002
ge11nn040000_e1d2031bdfea_000000000000_0000000000002
ge20nn040000_c3abebcf3d28_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn14enus_b8b6b186c967_000000000000_0000000000001
po11nn060000_8c1b2e3f6532_000000000000_0000000000001
ge11nn06zhcn_fb4afd1f380a_000000000000_0000000000001
he20nn020000_5594a17e7e7e_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
3:100;4:33554432;2:0|33488897|0|m,p,s,a Match?Exact match in Thumbprint's published controlled catalog captures: php-curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.2
1:4096;2:0;4:65535;5:16384;3:100;6:65536|16777216|0|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1.The fingerprint page shows the full measured match list. More on the catalog.1
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, +42 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (JA4T)

fingerprintco-occurrences
29200_2-4-8-1-3_1460_727

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36 QIHU 360SE15
Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.2623.112 Safari/537.364
Go-http-client/1.12
Mozilla/5.0 (compatible; The Lounge IRC Client; +https://github.com/thelounge/thelounge) facebookexternalhit/1.1 Twitterbot/1.02
SynologyChatBot/1.02
python-httpx/0.28.11
libredtail-http1
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.361
Turnitin (https://bit.ly/2UvnfoQ)1

Country

fingerprintco-occurrences
CN · China21
HK · Hong Kong SAR China2
KR · South Korea2
FR · France2
ZA · South Africa1
RU · Russia1
ID · Indonesia1
US · United States1
NL · Netherlands1

Network (ASN)

fingerprintco-occurrences
AS58461 · CT HangZhou IDC19
AS932 · XNNET LLC2
AS12322 · Free SAS2
AS9318 · SK Broadband Co Ltd2
AS37611 · AFRIHOST SP (PTY) LTD1
AS139971 · PT. Medialink Intercontinental1
AS50340 · JSC Selectel1
AS4134 · CHINANET BACKBONE1
AS46851 · Turnitin LLC1
AS197170 · TechTies Inc.1