TCP SYN (p0f)

4:42+22:0:1240:mss*52,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-08-05 05:58 · last seen 2026-10-30 13:50 · JSON

Last 7 days (1 observations)

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 TTL42+22
Options length0
MSS1240
Window sizemss*52
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
t13d1011h2_61a7ad8aa9b6_3fcd1a44f3e3 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28.The fingerprint page shows the full measured match list. More on the catalog.1
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.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 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.1
ge20nn020000_e5a56608905c_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.1
2:0;4:2097152;5:16384;6:16384|5177345|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.13.5, rust-reqwest 0.13.4, +4 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (JA4T)

fingerprintco-occurrences
64480_2-4-8-1-3_1240_102

User-Agent

fingerprintco-occurrences
WhatsApp/21
curl/8.21.01

Country

fingerprintco-occurrences
DE · Germany1
CZ · Czechia1

Network (ASN)

fingerprintco-occurrences
AS24940 · Hetzner Online GmbH1
AS49985 · IP4ISP z.s.p.o1

TLS supported groups

fingerprintco-occurrences
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