TCP SYN (p0f)

4:54+10:0:1460:mss*20,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-07-01 06:31 · last seen 2026-10-23 22:43 · JSON

Distinct clients per day (last 30 days, peak 40/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 TTL54+10
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
t13d3013h2_1d37bd780c83_8537cf56674e40
t12d700700_b8b0f76b4bb5_4446390ac2247
t13d1314h1_d8d503717f6d_82bceb9efa8b2
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.1
t12d650700_0dd215169a35_4446390ac2241

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_00000000000040
ge11nn050000_0b4164a3b800_000000000000_0000000000007
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.2
ge11nr030000_cd680697de12_000000000000_0000000000001
ge11nn040000_17807bc4167d_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.40

TCP SYN (JA4T)

fingerprintco-occurrences
29200_2-4-8-1-3_1460_751

User-Agent

fingerprintco-occurrences
curl/8.14.140
python-requests/2.6.0 CPython/2.7.5 Linux/3.10.0-1160.119.1.el7.x86_647
Go-http-client/1.11
libwww-perl/6.051
RSSPoller/1.01
python-requests/2.32.41

Country

fingerprintco-occurrences
GB · United Kingdom32
NL · Netherlands8
RS · Serbia7
US · United States2
CA · Canada1
HR · Croatia1

Network (ASN)

fingerprintco-occurrences
AS396356 · Latitude.sh32
AS49870 · Alsycon B.V.8
AS51430 · AltusHost B.V.7
AS14618 · Amazon.com, Inc.2
AS61211 · SETCOR d.o.o.1
AS32489 · Amanah Tech 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.40