TCP SYN (p0f)

4:39+25:0:1410:mss*30,8:mss,sok,ts,nop,ws,?34,nop,nop::0

first seen 2026-06-20 17:49 · last seen 2026-09-09 08:30 · JSON

Distinct clients per day (last 30 days, peak 3/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 TTL39+25
Options length0
MSS1410
Window sizemss*30
Window scale8
Options layoutmss,sok,ts,nop,ws,?34,nop,nop
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
t13d3112h1_e8f1e7e78f70_8d633dac712415
t13d3112h2_e8f1e7e78f70_8d633dac712411

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn040000_b221e026a664_000000000000_0000000000008
ge11nr060000_730b5c9702a1_000000000000_0000000000004
ge11nn050000_eb4e96aa336f_000000000000_0000000000004
ge11nn060000_3e7ded867bc2_000000000000_0000000000004
ge11nn050000_95d177640a65_000000000000_0000000000002
ge20nn050000_95d177640a65_000000000000_0000000000002
ge11nn060000_1bf4bdaf3068_000000000000_0000000000001
ge20nn040000_31537f9be9e0_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, +7 more.The fingerprint page shows the full measured match list. More on the catalog.11

TCP SYN (JA4T)

fingerprintco-occurrences
42300_2-4-8-1-3-34-1-1_1410_813

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (compatible; YandexBot/3.0; +http://yandex.com/bots)20
Mozilla/5.0 (compatible; YandexRenderResourcesBot/1.0; +http://yandex.com/bots) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.04
Mozilla/5.0 (compatible; YandexBot/3.0; +http://yandex.com/bots) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.02

Country

fingerprintco-occurrences
RU · Russia26

Network (ASN)

fingerprintco-occurrences
AS13238 · YANDEX LLC26