TCP SYN (p0f)

6:48+16:0:1440:mss*45,10:mss,sok,ts,nop,ws:flow:0

first seen 2026-07-02 14:02 · last seen 2026-10-31 10:21 · JSON

Last 7 days (7 observations)

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 version6
Initial TTL48+16
Options length0
MSS1440
Window sizemss*45
Window scale10
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
t12d290700_fc2078a0b8c0_8c06664c3ac550
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.3
t13d1517h2_8daaf6152771_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 155.0.1, firefox 154.0, firefox 156.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.3
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.2
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.1
t13d521100_b262b3658495_8e6e362c5eac1

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn040000_bfa5a9b89dd6_000000000000_00000000000022
ge11nn05en00_61812dc1cc58_000000000000_00000000000020
ge11nn06en00_3011d71998e2_000000000000_0000000000007
ge20nr12enus_a72b71f519fc_000000000000_0000000000003
ge20nn020000_e5a56608905c_000000000000_0000000000003
ge11nr040000_8391bea91fb6_000000000000_0000000000002
ge11nn030000_dd98166e0881_000000000000_0000000000001
ge20nr13enus_5907f7c6644a_000000000000_0000000000001
ge11nn07engb_71b742b5154a_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;4:131072;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.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
1:65536;2:0;4:131072;5:16384|12517377|7:0:0:42|m,p,a,s1
1:65536;2:0;4:131072;5:16384|12517377|5:0:0:42|m,p,a,s1

TCP SYN (JA4T)

fingerprintco-occurrences
64800_2-4-8-1-3_1440_1060

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (compatible; MJ12bot/v1.4.8; http://mj12bot.com/)50
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.363
Mozilla/5.0 (X11; Linux x86_64; rv:152.0) Gecko/20100101 Firefox/152.03
Mozilla/5.0 (compatible; authorized-security-scan)2
Mozilla/5.0 (compatible; The Lounge IRC Client; +https://github.com/thelounge/thelounge) facebookexternalhit/1.1 Twitterbot/1.01
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/149.0.0.0 Safari/537.36 Edg/149.0.0.01

Country

fingerprintco-occurrences
FR · France50
CH · Switzerland3
BR · Brazil3
NL · Netherlands2
US · United States1
GB · United Kingdom1

Network (ASN)

fingerprintco-occurrences
AS16276 · OVH SAS50
AS29222 · Infomaniak3
AS52772 · SJNET TELECOMUNICACOES - EIRELI3
AS51396 · Pfcloud UG2
AS16591 · Google Fiber Inc.1
AS12496 · IDNet1

TLS supported groups

fingerprintco-occurrences
001d,0017,0018 Match?Exact match in Thumbprint's published controlled catalog captures: rust-reqwest 0.12.28, rust-reqwest 0.11.27, winhttp 10.0.20348.1, +2 more.The fingerprint page shows the full measured match list. More on the catalog.4
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.2
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

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