TCP SYN (JA4T)

65535_2-1-3-1-1-4_1376_8

first seen 2026-08-03 19:44 · last seen 2026-08-31 05:15 · 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

TCP window65535
Option kinds2-1-3-1-1-4
MSS1376
Window scale8

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
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
t13d1617h2_86a278354501_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.3, +10 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.18.0, +9 more.The fingerprint page shows the full measured match list. More on the catalog.1
ge20nr13deat_9e2b86631664_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:42|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 152.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
6:48+16:0:1376:65535,8:mss,nop,ws,nop,nop,sok:flow:01
4:112+16:0:1376:65535,8:mss,nop,ws,nop,nop,sok:df,id+:01

User-Agent

fingerprintco-occurrences
curl/8.5.01
Mozilla/5.0 (Android 14; Mobile; rv:153.0) Gecko/153.0 Firefox/153.01

Country

fingerprintco-occurrences
US · United States1
AT · Austria1

Network (ASN)

fingerprintco-occurrences
AS8447 · A1 Telekom Austria AG1
AS21928 · T-Mobile USA, Inc.1