TCP SYN (p0f)

4:122+6:0:1420:mss*46,8:mss,nop,ws,nop,nop,sok:df,id+,ecn:0

first seen 2026-06-30 12:27 · last seen 2026-10-23 12:23 · 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 TTL122+6
Options length0
MSS1420
Window sizemss*46
Window scale8
Options layoutmss,nop,ws,nop,nop,sok
Quirksdf,id+,ecn
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
t13d1411h2_cbb2034c60b8_e7c28522265151
t12d860600_e18388e7f3a3_a1e93568279517
t13d1311h2_f57a46bbacb6_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.23.12, go-net/http 1.24.13.The fingerprint page shows the full measured match list. More on the catalog.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr020000_fb4f949fd323_000000000000_00000000000051
ge11nn06enus_ff6fe191b79d_000000000000_00000000000017
ge20nr020000_b89ce445e0b3_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
2:0;4:4194304;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, go-net/http 1.23.12.The fingerprint page shows the full measured match list. More on the catalog.51
2:0;4:4194304;5:16384;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.10, go-net/http 1.26.9, +8 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (JA4T)

fingerprintco-occurrences
65320_2-1-3-1-1-4_1420_869

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (compatible; CMS-Checker/1.0; +https://example.com)30
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.3621
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.3612
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.364
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.361
Go-http-client/2.01

Country

fingerprintco-occurrences
US · United States56
BE · Belgium7
NL · Netherlands6

Network (ASN)

fingerprintco-occurrences
AS396982 · Google LLC69

TLS supported groups

fingerprintco-occurrences
001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13.The fingerprint page shows the full measured match list. More on the catalog.5