TCP SYN (p0f)

4:51+13:0:1420:mss*46,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-22 03:34 · last seen 2026-09-05 18:39 · 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 version	`4`
Initial TTL	`51+13`
Options length	`0`
MSS	`1420`
Window size	`mss*46`
Window scale	`7`
Options layout	`mss,sok,ts,nop,ws`
Quirks	`df,id+`
Payload class	`0`

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)

fingerprint	co-occurrences
`t13d1516h2_8daaf6152771_d8a2da3f94cd` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, chrome 149.0.7827.156, +25 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`t13d131100_f57a46bbacb6_ab7e3b40a677` Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.5, go-net/http 1.26.4.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP request (JA4H)

fingerprint	co-occurrences
`ge20nr13enus_54728652be35_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: chromium 149.0.7827.102, chrome 149.0.7827.102, edge 149.0.4022.52, +10 more.The fingerprint page shows the full measured match list. More on the catalog.	1
`ge11nn030000_cd680697de12_000000000000_000000000000` Match?Exact match in Thumbprint's published controlled catalog captures: powershell 7.6.5, powershell 7.6.4, go-net/http 1.27.0, +7 more.The fingerprint page shows the full measured match list. More on the catalog.	1

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`1:65536;2:0;4:6291456;6:262144\|15663105\|1:1:0:220\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chromium 149.0.7827.102, chrome 149.0.7827.102, +59 more.The fingerprint page shows the full measured match list. More on the catalog.	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`65320_2-4-8-1-3_1420_7`	1

User-Agent

fingerprint	co-occurrences
`Hello from Palo Alto Networks, find out more about our scans in https://docs-cortex.paloaltonetworks.com/r/1/Cortex-Xpanse/Scanning-activity`	1
`Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.36 PTST/26.03`	1

Country

fingerprint	co-occurrences
`US` · United States	1
`TW` · Taiwan	1

Network (ASN)

fingerprint	co-occurrences
`AS396982` · Google LLC	2

Cross-transport links

TLS ClientHello fingerprints observed from the same client via the beacon's correlation id on the other transport (e.g. this stack over TCP ↔ that stack over QUIC).

fingerprint	linked observations
`q13d0311h3_55b375c5d22e_653d80c3fe9d`	1