TCP SYN (p0f)

4:43+21:0:1460:mss*44,8:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-07-01 14:34 · last seen 2026-10-23 22:36 · JSON

Distinct clients per day (last 30 days, peak 5/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 TTL43+21
Options length0
MSS1460
Window sizemss*44
Window scale8
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
t13d3013h2_1d37bd780c83_8537cf56674e5
t13d190900_9dc949149365_97f8aa674fd93
t13d4312h1_c7886603b240_b26ce05bbdd62
t12d1609h2_8cdfa2d4673b_f9c1bad5661c1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_0000000000005
ge11nn050000_b223a0ebb0b5_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: python-requests 2.34.2, python-requests 2.33.1, python-requests 2.32.3.The fingerprint page shows the full measured match list. More on the catalog.2
ge11nn07*000_b23b8373b424_000000000000_0000000000002
he20nn010000_a510e5066512_000000000000_0000000000001
ge11nn08*000_d55d57da3167_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.5
2:0;4:4194304;6:8192|1073741824|0|a,m,p,s1

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_811

User-Agent

fingerprintco-occurrences
curl/8.14.15
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.62 Safari/537.363
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.67 Safari/537.361

Country

fingerprintco-occurrences
DE · Germany4
FR · France4
BR · Brazil1
GB · United Kingdom1
RS · Serbia1

Network (ASN)

fingerprintco-occurrences
AS45102 · Alibaba (US) Technology Co., Ltd.5
AS16276 · OVH SAS4
AS31042 · Yettel d.o.o.1
AS28126 · BRISANET SERVICOS DE TELECOMUNICACOES S.A1

TLS supported groups

fingerprintco-occurrences
11ec,001d,0017,001e,0018,0019,0100,0101 Match?Exact match in Thumbprint's published controlled catalog captures: node-fetch 24.22.1, python-httpx 0.28.1, python-requests 2.34.2, +2 more.The fingerprint page shows the full measured match list. More on the catalog.5
001d,0017,001e,0019,0018,0100,0101,0102,0103,0104 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0, php-guzzle 8.3.1, curl 7.88.1, +10 more.The fingerprint page shows the full measured match list. More on the catalog.2