TCP SYN (p0f)

4:45+19:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-19 13:42 · last seen 2026-09-03 09:28 · 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 TTL45+19
Options length0
MSS1460
Window sizemss*44
Window scale10
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
t13d3112h1_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: php-guzzle 8.1.0, php-guzzle 8.0.2, php-guzzle 7.14.2, +6 more.The fingerprint page shows the full measured match list. More on the catalog.16
t13d1617h2_86a278354501_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.3, +10 more.The fingerprint page shows the full measured match list. More on the catalog.13
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.5
t13d1517h2_8daaf6152771_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 154.0.1, firefox 155.0.1, +1 more.The fingerprint page shows the full measured match list. More on the catalog.3
t13d3112h2_e8f1e7e78f70_b26ce05bbdd6 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.5.0, php-curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.2
t13d4113h2_8ae0994cad11_86f67be995ff1
t12d200700_22c523c4c553_2dae41c691ec1
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
t13d3713h2_db35923f8641_7c76daad20ec Match?Exact match in Thumbprint's published controlled catalog captures: java-httpclient 23.0.2, java-httpclient 22.0.2.The fingerprint page shows the full measured match list. More on the catalog.1
t13d1514h2_8daaf6152771_a5b99884f7f51

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn030000_fe444ad14866_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.16.0.The fingerprint page shows the full measured match list. More on the catalog.16
ge20nr11enus_3901d4197baf_000000000000_00000000000012
ge20nr11ruru_187a9385d229_000000000000_0000000000004
ge20nr12engb_f8a3a1e39dc3_000000000000_0000000000003
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.18.0, +9 more.The fingerprint page shows the full measured match list. More on the catalog.3
ge20nn13engb_9519c2577190_000000000000_0000000000001
ge11nr030000_cd680697de12_000000000000_0000000000001
ge20nn030000_042112399351_000000000000_000000000000 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.1
ge11nn040000_cf1edba2959c_000000000000_0000000000001
ge20nn030000_ff50983941c1_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 154.0, +25 more.The fingerprint page shows the full measured match list. More on the catalog.3
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, +7 more.The fingerprint page shows the full measured match list. More on the catalog.2
1:65536;2:0;4:6291456;6:262144|15663105|1:1:0:256|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 131.0.6778.33, chromium 151.0.7922.34, chrome 151.0.7922.137, +43 more.The fingerprint page shows the full measured match list. More on the catalog.2
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.2
1:65536;2:0;4:131072;5:16384|12517377|3:0:0:42|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 152.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.2
3:100;4:10485760;2:0|1048510465|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0.The fingerprint page shows the full measured match list. More on the catalog.2
1:16384;2:1;3:100;4:16777216;5:16384|33488897|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: java-httpclient 22.0.2.The fingerprint page shows the full measured match list. More on the catalog.1
1:65536;2:0;4:6291456;6:262144|15663105|3:1:0:220|m,a,s,p Match?Exact match in Thumbprint's published controlled catalog captures: chromium 151.0.7922.34, chromium 147.0.7727.15, chromium 145.0.7632.6, +21 more.The fingerprint page shows the full measured match list. More on the catalog.1
4:16777216|16711681|0|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|7:0:0:42|m,p,a,s1

TCP SYN (JA4T)

fingerprintco-occurrences
64240_2-4-8-1-3_1460_1045

User-Agent

fingerprintco-occurrences
curl/8.5.018
Mozilla/5.0 (X11; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.014
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.365
Mozilla/5.0 (X11; Linux x86_64; rv:154.0) Gecko/20100101 Firefox/154.04
Go-http-client/1.11
Mozilla/5.01
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.361
TheSocleAgent/2.0 (+https://thesocle.net)1
Mozilla/5.0 (compatible; RssArchiver/1.0; +https://rssarchiver.thesocle.net)1
curl/8.21.01

Country

fingerprintco-occurrences
US · United States18
NL · Netherlands15
EE · Estonia4
RU · Russia4
AU · Australia2
FR · France2
JP · Japan1
TH · Thailand1

Network (ASN)

fingerprintco-occurrences
AS11351 · Charter Communications Inc18
AS31615 · Odido Netherlands B.V.15
AS2586 · Elisa Eesti AS4
AS31430 · OOO Suntel4
AS16276 · OVH SAS2
AS7545 · TPG Telecom Limited1
AS206092 · F.N.S. HOLDINGS LIMITED1
AS45102 · Alibaba (US) Technology Co., Ltd.1
AS38195 · Superloop1

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).

fingerprintlinked observations
q13d0311h3_55b375c5d22e_653d80c3fe9d3
q13d0315h3_55b375c5d22e_dc5437974b471