TCP SYN (p0f)

4:55+9:0:1452:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df,ecn:0

first seen 2026-09-22 09:27 · last seen 2026-10-18 17:53 · 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 TTL55+9
Options length0
MSS1452
Window size65535
Window scale6
Options layoutmss,nop,ws,nop,nop,ts,sok,eol+1
Quirksdf,ecn
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
t13d1516h2_8daaf6152771_d8a2da3f94cd Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d4312h1_c7886603b240_b26ce05bbdd61
t13d1516h2_8daaf6152771_806a8c22fdea Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 151.0.7922.137, chromium 151.0.7922.34, +28 more.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr12enus_54b4638ab28b_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 152.0.7977.83, chrome 151.0.7922.137, +61 more.The fingerprint page shows the full measured match list. More on the catalog.1
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.1
ge20nr13enus_05d774e75578_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
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, +85 more.The fingerprint page shows the full measured match list. More on the catalog.2

TCP SYN (JA4T)

fingerprintco-occurrences
65535_2-1-3-1-1-8-4-0-0_1452_63

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/153.0.0.0 Safari/537.361

Country

fingerprintco-occurrences
IT · Italy2
DE · Germany1

Network (ASN)

fingerprintco-occurrences
AS43989 · Ehinet Srl2
AS3320 · Deutsche Telekom AG1

TLS supported groups

fingerprintco-occurrences
001d,0017,001e,0019,0018,0100,0101,0102,0103,0104 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, php-guzzle 8.3.1, curl 7.88.1, +10 more.The fingerprint page shows the full measured match list. More on the catalog.1

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprintlinked observations
q13d0311h3_55b375c5d22e_653d80c3fe9d2