TCP SYN (p0f)

4:39+25:0:1412:mss*23,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-09-24 10:57 · last seen 2026-10-15 11:45 · 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 TTL39+25
Options length0
MSS1412
Window sizemss*23
Window scale7
Options layoutmss,sok,ts,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
t13d131000_f57a46bbacb6_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.2

HTTP request (JA4H)

fingerprintco-occurrences
ge11nr05zhcn_f3bb7aa45ec4_000000000000_0000000000002

TCP SYN (JA4T)

fingerprintco-occurrences
32476_2-4-8-1-3_1412_72

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/537.36 Edg/120.0.0.02

Country

fingerprintco-occurrences
US · United States2

Network (ASN)

fingerprintco-occurrences
AS135377 · UCLOUD INFORMATION TECHNOLOGY (HK) LIMITED2

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 157.0.1, firefox-esr 153.5.1esr, firefox 158.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.1