TCP SYN (p0f)

4:45+19:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-11 07:20 · last seen 2026-11-01 18:05 · JSON

Last 7 days (47 observations)

Distinct clients per day (last 30 days, peak 191/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 TTL45+19
Options length0
MSS1460
Window sizemss*44
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
t13d3013h2_1d37bd780c83_8537cf56674e Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.18.0.The fingerprint page shows the full measured match list. More on the catalog.200
t13d311100_e8f1e7e78f70_d41ae481755e Match?Exact match in Thumbprint's published controlled catalog captures: rust-hyper 1.11.1, rust-hyper 1.12.0, rust-hyper 1.11.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.117
t13d4312h1_c7886603b240_b26ce05bbdd690
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.82
t13d4412h1_fd39b124ee10_58ed7828516f66
t13d1515h1_8daaf6152771_de4a06bb82e339
t13d1515h1_8daaf6152771_0a20fe35d3a523
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.16
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.14
t13d1516h2_8daaf6152771_02713d6af862 Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 134.0.6998.35, chromium 133.0.6943.16.The fingerprint page shows the full measured match list. More on the catalog.12

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_000000000000199
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.156
ge11nr040000_177aea7101ae_000000000000_000000000000114
ge20nn13enus_0c2c1d640f3e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 151.0.7922.137, chrome 151.0.7922.170, chrome 151.0.7922.108, +39 more.The fingerprint page shows the full measured match list. More on the catalog.85
ge11nn13enus_9db22d02e17a_000000000000_00000000000054
ge20nn04enus_989c7cc05c9b_000000000000_00000000000024
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.16
ge11nr040000_e1d2031bdfea_000000000000_00000000000014
ge11nn05enus_f3bb7aa45ec4_000000000000_00000000000012
ge11nn14enus_4a2973d235de_000000000000_00000000000012

HTTP/2 frames (Akamai)

fingerprintco-occurrences
3:100;4:65536;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, curl 8.18.0, curl 8.21.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.200
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, +60 more.The fingerprint page shows the full measured match list. More on the catalog.91
1:65536;2:0;4:6291456;6:262144;4:1048576|15663105|1:0:0:256|m,a,s,p24
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, +85 more.The fingerprint page shows the full measured match list. More on the catalog.13
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.11
2:0;4:4194304;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.9
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, curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.3
3:100;4:1073741824;2:0|1073676289|0|m,p,s,a3
1:65536;2:0;3:1000;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p2
1:65536;3:1000;4:6291456|15663105|1:1:0:256|m,a,s,p2

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_7773

User-Agent

fingerprintco-occurrences
curl/8.14.1200
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/150.0.0.0 Safari/537.3682
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.3631
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.3627
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.3617
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.3616
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.3615
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.3615
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.3614
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3613

Country

fingerprintco-occurrences
SG · Singapore128
US · United States104
NL · Netherlands99
GB · United Kingdom89
FR · France40
DE · Germany32
UA · Ukraine19
CO · Colombia19
ES · Spain17
IT · Italy17

Network (ASN)

fingerprintco-occurrences
AS45102 · Alibaba (US) Technology Co., Ltd.125
AS12876 · Scaleway SAS101
AS8560 · IONOS SE76
AS64249 · Charles River Operation47
AS9009 · M247 Europe SRL29
AS16276 · OVH SAS24
AS58087 · Florian Kolb18
AS12479 · Orange Espagne SA17
AS12874 · Fastweb SpA14
AS24940 · Hetzner Online GmbH12

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,001e,0018,0019,0100,0101 Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1, python-requests 2.34.2, curl 8.23.0, +4 more.The fingerprint page shows the full measured match list. More on the catalog.212
001d,0017,001e,0019,0018,0100,0101,0102,0103,0104 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, php-guzzle 8.3.1, curl 7.88.1, +10 more.The fingerprint page shows the full measured match list. More on the catalog.150
11ec,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 158.0.1, firefox 157.0, firefox 157.0.1, +5 more.The fingerprint page shows the full measured match list. More on the catalog.14
0a0a,001d,0017,001811
0a0a,11ec,001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 156.0.8078.48, edge 155.0.4283.62, chrome 156.0.8078.47, +11 more.The fingerprint page shows the full measured match list. More on the catalog.7
0017,0018,00195
001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.4
001d,0017,001e,0019,00182
001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, winhttp 10.0.20348.1, +2 more.The fingerprint page shows the full measured match list. More on the catalog.1
11ec,001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 156.0.8078.48, edge 155.0.4283.62, chrome 156.0.8078.47, +11 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).

fingerprintlinked observations
q13d0312h3_55b375c5d22e_178839b6cec11