TCP SYN (p0f)

4:57+7:0:1460:65535,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-07-01 18:29 · last seen 2026-10-21 15:59 · JSON

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 TTL57+7
Options length0
MSS1460
Window size65535
Window scale10
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
t13d3113h2_e8f1e7e78f70_ce5650b735ce3
t13d1517h2_8daaf6152771_dcad5a0539913
t13d1812h1_85036bcba153_b26ce05bbdd61
t13d5212h1_b262b3658495_8e6e362c5eac Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 24.21.0, node-fetch 24.19.0, node-fetch 22.23.1, +8 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d3112h2_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.5.0, php-curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.1
t12d280900_0df5e5c63df4_5c2ba26727241
t13d2013h1_2b729b4bf6f3_e24568c0d4401

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr05enus_d0c4616abeb5_000000000000_0000000000004
ge20nr12dede_f8a3a1e39dc3_000000000000_0000000000002
ge11nn030000_fe444ad14866_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.16.0, curl 7.88.1, curl 8.21.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn07enus_6f5b1826d533_000000000000_0000000000001
ge10nr040000_532a1ee47909_000000000000_0000000000001
ge20nn14dede_3920ee50bd52_000000000000_0000000000001
ge20nn06*000_a84fcfa3ad59_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, curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.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;4:6291456;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.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
2:0;4:262144|458753|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 26.4.0.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (JA4T)

fingerprintco-occurrences
65535_2-4-8-1-3_1460_1011

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.363
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.362
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.362
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.361
IndexaroLeadBot/0.1 (+https://indexaro.com; polite startup discovery)1
curl/8.21.01

Country

fingerprintco-occurrences
US · United States5
DE · Germany3
GB · United Kingdom3

Network (ASN)

fingerprintco-occurrences
AS64080 · SYN LTD3
AS55286 · B2 Net Solutions Inc.3
AS12586 · GHOSTnet GmbH3
AS62240 · Clouvider1
AS11492 · CABLE ONE, INC.1

TLS supported groups

fingerprintco-occurrences
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