TCP SYN (p0f)

4:43+21:0:1398:mss*44,7:mss,sok,nop,nop,nop,nop,nop,nop,nop,nop,nop,nop,nop,ws:df,id+:0

first seen 2026-06-29 18:51 · last seen 2026-09-09 10:30 · 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 TTL43+21
Options length0
MSS1398
Window sizemss*44
Window scale7
Options layoutmss,sok,nop,nop,nop,nop,nop,nop,nop,nop,nop,nop,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
t13d1516h2_8daaf6152771_02713d6af862 Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 134.0.6998.35, chromium 133.0.6943.16.The fingerprint page shows the full measured match list. More on the catalog.4

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr14en00_c2507efc711e_000000000000_0000000000003
ge20nn14en00_c2507efc711e_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;3:1000;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p4

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-1-1-1-1-1-1-1-1-1-1-1-3_1398_73

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.364

Country

fingerprintco-occurrences
CN · China4

Network (ASN)

fingerprintco-occurrences
AS4134 · CHINANET BACKBONE4