TCP SYN (p0f)

6:54+10:0:1440:mss*45,7:mss,sok,ts,nop,ws:flow:0

first seen 2026-06-26 09:40 · last seen 2026-10-23 22:45 · JSON

Distinct clients per day (last 30 days, peak 37/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 TTL54+10
Options length0
MSS1440
Window sizemss*45
Window scale7
Options layoutmss,sok,ts,nop,ws
Quirksflow
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_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.39
t13d1715h2_5b57614c22b0_a54fffd0eb6114
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.6
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.2
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
t13d2013h2_a09f3c656075_7f0f34a4126d Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.4, +2 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d2013h1_2b729b4bf6f3_e24568c0d4401

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_00000000000037
ge20nn020000_5594a17e7e7e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.7.1, curl 8.5.0, curl 8.13.0, +11 more.The fingerprint page shows the full measured match list. More on the catalog.8
ge20nn12enus_a72b71f519fc_000000000000_0000000000006
ge20nr11enus_187a9385d229_000000000000_0000000000004
ge20nr13enus_44e1f6d71293_000000000000_0000000000002
ge20nr100000_9e93078f8017_000000000000_0000000000001
ge20cn110000_d6b8ff49a7f0_dcaae5b74b2e_f16bac0ad8481
ge11nr030000_cd680697de12_000000000000_0000000000001
ge20nn08enus_1945e0741196_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.4.The fingerprint page shows the full measured match list. More on the catalog.1
ge11nn030000_fe444ad14866_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: curl 8.16.0, curl 7.88.1, curl 8.21.0, +1 more.The fingerprint page shows the full measured match list. More on the catalog.1

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.39
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.5
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 155.0.1, +32 more.The fingerprint page shows the full measured match list. More on the catalog.4
3:100;4:33554432;2:0|33488897|0|m,p,s,a Match?Exact match in Thumbprint's published controlled catalog captures: php-curl 7.88.1, curl 7.88.1.The fingerprint page shows the full measured match list. More on the catalog.3
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.3
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, +60 more.The fingerprint page shows the full measured match list. More on the catalog.1
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 152.0.7977.83, +85 more.The fingerprint page shows the full measured match list. More on the catalog.1
2:0;3:100;4:2097152;9:1|10420225|0|m,s,a,p Match?Exact match in Thumbprint's published controlled catalog captures: safari 26.5.2, safari 26.6.2, safari 26.5, +3 more.The fingerprint page shows the full measured match list. More on the catalog.1
1:65536;2:0;4:131072;5:16384|12517377|9:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|11:0:0:42|m,p,a,s1

TCP SYN (JA4T)

fingerprintco-occurrences
64800_2-4-8-1-3_1440_762

User-Agent

fingerprintco-occurrences
curl/8.14.139
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.014
curl/8.5.03
curl/7.88.13
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.362
Go-http-client/1.11
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/601.2.4 (KHTML, like Gecko) Version/9.0.1 Safari/601.2.4 facebookexternalhit/1.1 Facebot Twitterbot/1.01
curl/8.21.01

Country

fingerprintco-occurrences
LT · Lithuania33
US · United States21
RU · Russia5
DE · Germany2
IN · India2
HK · Hong Kong SAR China1

Network (ASN)

fingerprintco-occurrences
AS61272 · UAB Bacloud33
AS62744 · Quintex Alliance Consulting14
AS12389 · PJSC Rostelecom5
AS701 · Verizon Business3
AS141995 · Contabo Asia Private Limited2
AS16276 · OVH SAS2
AS44486 · synlinq.de2
AS22773 · Cox Communications Inc.1
AS36183 · Akamai Technologies, Inc.1
AS139659 · LUCIDACLOUD LIMITED1

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.37

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_653d80c3fe9d1