TCP SYN (p0f)

6:37+27:0:1380:65535,8:mss,sok,ts,nop,ws::0

first seen 2026-08-29 06:54 · last seen 2026-08-29 06:54 · 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 version6
Initial TTL37+27
Options length0
MSS1380
Window size65535
Window scale8
Options layoutmss,sok,ts,nop,ws
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
t13d3111h2_e8f1e7e78f70_5ac7197df9d21

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn040000_3dccbaa13f05_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:4096;2:0;5:16384;6:131072;3:100;4:65536|26148865|0|m,s,p,a1

TCP SYN (JA4T)

fingerprintco-occurrences
65535_2-4-8-1-3_1380_81

User-Agent

fingerprintco-occurrences
facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php)1

Country

fingerprintco-occurrences
US · United States1

Network (ASN)

fingerprintco-occurrences
AS32934 · Facebook, Inc.1