TCP SYN (p0f)

4:44+20:0:1460:mss*44,14:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-08-03 07:54 · last seen 2026-10-23 22:44 · JSON

Distinct clients per day (last 30 days, peak 17/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 TTL44+20
Options length0
MSS1460
Window sizemss*44
Window scale14
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.17
t12d210700_76e208dd3e22_2dae41c691ec1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_00000000000017
ge11nn12enus_d9dcce99a5ac_000000000000_0000000000001

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.17

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_1418

User-Agent

fingerprintco-occurrences
curl/8.14.117
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36 Edg/149.0.0.01

Country

fingerprintco-occurrences
RO · Romania6
AU · Australia2
CH · Switzerland2
GB · United Kingdom2
EE · Estonia2
NO · Norway1
RU · Russia1
PL · Poland1
KE · Kenya1

Network (ASN)

fingerprintco-occurrences
AS9009 · M247 Europe SRL6
AS16276 · OVH SAS3
AS51852 · Private Layer INC2
AS136557 · Host Universal Pty Ltd2
AS1257 · Tele2 Sverige AB2
AS212667 · RECONN LLC1
AS34989 · ServeTheWorld AS1
AS327813 · Host Africa (Pty) Ltd1

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.17