TCP SYN (p0f)

4:57+7:0:1460:mss*29,9:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-12 15:29 · last seen 2026-10-26 23:04 · JSON

Last 7 days (21 observations)

Distinct clients per day (last 30 days, peak 8/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 TTL57+7
Options length0
MSS1460
Window sizemss*29
Window scale9
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
t13d3515h1_8f004308c246_5c2c66f702b043
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.16
t13d3013h2_1d37bd780c83_8537cf56674e Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.18.0.The fingerprint page shows the full measured match list. More on the catalog.8
t13d351400_8f004308c246_5c2c66f702b07
t13d1312h1_f57a46bbacb6_ab7e3b40a6773
t13d141100_cbb2034c60b8_e5728521abd42
t13i131000_f57a46bbacb6_e5728521abd41

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn050000_a1c329e38462_000000000000_00000000000048
ge11nn130000_7f254152a55f_000000000000_00000000000016
ge20nn030000_bf75ddd0bb29_000000000000_0000000000008
ge11nn030000_cd680697de12_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: powershell 7.6.6, powershell 7.6.5, powershell 7.6.4, +11 more.The fingerprint page shows the full measured match list. More on the catalog.2
ge11nn040000_e1d2031bdfea_000000000000_0000000000002
po11nn080000_86f5668e3d93_000000000000_0000000000002
ge11nn030000_042112399351_000000000000_0000000000001
ge11nn050000_fba061adb361_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
3:100;4:65536;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, curl 8.18.0, curl 8.21.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.8

TCP SYN (JA4T)

fingerprintco-occurrences
42340_2-4-8-1-3_1460_979

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (compatible; Infrawatch/1.0; +https://infrawat.ch/)50
curl/8.14.18
Mozilla/5.03
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.363
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.362
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.362
Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)2
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.2 Safari/605.1.152
Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Mobile Safari/537.362
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36 Edg/130.0.0.02

Country

fingerprintco-occurrences
NL · Netherlands70
DE · Germany5
GB · United Kingdom2
US · United States1
SE · Sweden1
IT · Italy1

Network (ASN)

fingerprintco-occurrences
AS25369 · Hydra Communications Ltd50
AS48090 · TECHOFF SRV LIMITED21
AS41436 · Kamatera Inc3
AS36007 · Kamatera, Inc.2
AS210329 · Kamatera Inc2
AS14987 · Rethem Hosting LLC1
AS57043 · HOSTKEY B.V.1

TLS supported groups

fingerprintco-occurrences
11ec,11eb,11ed,001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.3, go-net/http 1.26.10.The fingerprint page shows the full measured match list. More on the catalog.19
11ec,001d,0017,001e,0018,0019,0100,0101 Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1, python-requests 2.34.2, curl 8.23.0, +4 more.The fingerprint page shows the full measured match list. More on the catalog.8
001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.2