TCP SYN (JA4T)

27600_2-4-8-1-3_1380_7

first seen 2026-10-04 16:10 · last seen 2026-10-04 16:10 · 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

TCP window27600
Option kinds2-4-8-1-3
MSS1380
Window scale7

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
t13d1517h2_8daaf6152771_dcad5a0539912
t13d1717h2_5b57614c22b0_68c5a8c2958d2

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn13enus_1d953776a77e_000000000000_0000000000002
ge20nr13kokr_1d953776a77e_000000000000_0000000000001
ge20nn10kokr_71a24014cdf5_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +60 more.The fingerprint page shows the full measured match list. More on the catalog.2
1:65536;2:0;4:131072;5:16384|12517377|1:0:0:42|m,p,a,s2

TCP SYN (p0f)

fingerprintco-occurrences
4:49+15:0:1380:mss*20,7:mss,sok,ts,nop,ws:df,id+:03
4:48+16:0:1380:mss*20,7:mss,sok,ts,nop,ws:df,id+:01

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Safari/537.362
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:147.0) Gecko/20100101 Firefox/147.01

Country

fingerprintco-occurrences
CN · China4

Network (ASN)

fingerprintco-occurrences
AS4134 · CHINANET BACKBONE2
AS4837 · CHINA UNICOM China169 Backbone2