TCP SYN (p0f)

4:101+27:0:1440:65535,8:mss,nop,ws,nop,nop,sok:df,id+:0

first seen 2026-06-27 13:07 · last seen 2026-09-16 00:59 · JSON

Last 7 days (1 observations)

Distinct clients per day (last 30 days, peak 2/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 TTL101+27
Options length0
MSS1440
Window size65535
Window scale8
Options layoutmss,nop,ws,nop,nop,sok
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
t13d201100_2b729b4bf6f3_36bf25f296df63
t13d1812h1_85036bcba153_d41ae481755e6
t13d181100_85036bcba153_d41ae481755e1

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn16enus_a27292610b04_000000000000_00000000000046
ge11nn010000_4a823118b9ba_000000000000_00000000000016
ge11nn050000_3658ef221638_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: wget 1.21.4, wget 1.21.3, wget 1.25.0.The fingerprint page shows the full measured match list. More on the catalog.3
ge11nn060000_a284f3d85baf_000000000000_0000000000002
ge11nn010000_4740ae6347b0_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: rust-hyper 1.11.0, rust-hyper 1.11.1, rust-hyper 1.10.1.The fingerprint page shows the full measured match list. More on the catalog.1
po11nr10enus_af6b54c809f5_000000000000_0000000000001
ge11nn06enus_a89d28968959_000000000000_0000000000001

TCP SYN (JA4T)

fingerprintco-occurrences
65535_2-1-3-1-1-4_1440_869

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3646
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.363
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.362
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.01

Country

fingerprintco-occurrences
IT · Italy41
NO · Norway16
SE · Sweden7
CH · Switzerland3
JP · Japan2
HK · Hong Kong SAR China1

Network (ASN)

fingerprintco-occurrences
AS8075 · Microsoft Corporation70