TCP SYN (p0f)

4:46+18:0:1360:mss*48,7:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-11 23:08 · last seen 2026-10-23 22:31 · 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 TTL46+18
Options length0
MSS1360
Window sizemss*48
Window scale7
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
t13d191000_9dc949149365_e7c28522265126
t13d3112h2_e8f1e7e78f70_6bebaf5329ac Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.13.0.The fingerprint page shows the full measured match list. More on the catalog.2
t13d311100_1d947a95fc68_b72e173852fa2
t13d491200_bd868743f55c_7c76daad20ec Match?Exact match in Thumbprint's published controlled catalog captures: java-urlconnection 17.0.12.The fingerprint page shows the full measured match list. More on the catalog.2
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.1
t13d0711h2_c4a653911898_9ced094328c91
t13d0811h2_0eeac54902ac_9ced094328c91

HTTP request (JA4H)

fingerprintco-occurrences
ge11nr050000_a1c329e38462_000000000000_00000000000026
ge11nn050000_901565333b7c_000000000000_0000000000002
ge11nn050000_956597cbd3ef_000000000000_0000000000002
he20cr07enus_3c34c2a3e1d9_55a15b6e0024_7439440d66fb2
ge20nn04enus_989c7cc05c9b_000000000000_0000000000002
ge20nn030000_bf75ddd0bb29_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.3
1:65536;2:0;4:6291456;6:262144;4:1048576|15663105|1:0:0:256|m,a,s,p2

TCP SYN (JA4T)

fingerprintco-occurrences
65280_2-4-8-1-3_1360_729

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3626
SiteCheckerBotCrawler/1.0 (+http://sitechecker.pro)4
Linux / Firefox 29: Mozilla/5.0 (X11; Linux x86_64; rv:29.0) Gecko/20100101 Firefox/29.02
curl/8.14.11
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.4 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.2 Safari/537.361

Country

fingerprintco-occurrences
NL · Netherlands25
DE · Germany7
GB · United Kingdom1
LT · Lithuania1
XK · Kosovo1

Network (ASN)

fingerprintco-occurrences
AS213790 · Limited Network LTD27
AS24940 · Hetzner Online GmbH6
AS208137 · Feo Prest SRL1
AS213900 · RS Computers L.L.C1

TLS supported groups

fingerprintco-occurrences
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.1