TCP SYN (p0f)

4:48+16:0:1460:mss*29,12:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-08-29 18:17 · last seen 2026-10-29 17:15 · JSON

Last 7 days (16 observations)

Distinct clients per day (last 30 days, peak 613/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 TTL48+16
Options length0
MSS1460
Window sizemss*29
Window scale12
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_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.643
t13d191000_9dc949149365_e7c285222651116
t12d4906h1_730fb1b0ac6a_22a92d800fe491
t13d1517h2_8daaf6152771_cb7bf5808d99 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 152.0.7977.83, chrome 156.0.8078.48, chrome 154.0.8037.57, +27 more.The fingerprint page shows the full measured match list. More on the catalog.15
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.10
t13d4312h1_c7886603b240_b26ce05bbdd67
t13d1011h2_18ef40b21276_879711aa9f164
t13d131100_f57a46bbacb6_f50d94e863eb Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.27.1, go-net/http 1.27.3, go-net/http 1.27.0, +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.1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn030000_bf75ddd0bb29_000000000000_000000000000643
ge11nn040000_8391bea91fb6_000000000000_000000000000116
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.98
ge20nr13enus_0c2c1d640f3e_000000000000_0000000000009
ge20nr12enus_54b4638ab28b_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 150.0.7871.187, chrome 152.0.7977.83, chrome 151.0.7922.137, +61 more.The fingerprint page shows the full measured match list. More on the catalog.4
ge11nr010000_4a823118b9ba_000000000000_0000000000004
ge20nn14enus_068ebe3632ec_000000000000_0000000000002
ge20nn13enus_0c2c1d640f3e_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: chrome 151.0.7922.137, chrome 151.0.7922.170, chrome 151.0.7922.108, +39 more.The fingerprint page shows the full measured match list. More on the catalog.2
po20nn23enus_91c53b5c6d06_000000000000_0000000000001
po20nn15enus_6175c8d80ef7_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.643
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.5
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.4
0|00|0|m,s,a,p4
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.1
1:65536;2:0;4:6291456;6:262144|15663105|3:1:0:256|m,a,s,p1
1:65536;2:0;4:6291456;6:262144|15663105|7:1:0:256|m,a,s,p1
1:65536;2:0;4:6291456;6:262144|15663105|5:1:0:256|m,a,s,p1
1:65536;2:0;4:6291456;6:262144|15663105|9:1:0:256|m,a,s,p1
1:65536;2:0;4:6291456;6:262144|15663105|11:1:0:256|m,a,s,p1

TCP SYN (JA4T)

fingerprintco-occurrences
42340_2-4-8-1-3_1460_12890

User-Agent

fingerprintco-occurrences
curl/8.14.1643
python-requests/2.27.175
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.3616
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.3615
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.3615
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:129.0) Gecko/20100101 Firefox/129.015
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:129.0) Gecko/20100101 Firefox/129.015
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.3614
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.1514
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36 Edg/128.0.0.014

Country

fingerprintco-occurrences
DE · Germany640
NL · Netherlands226
SG · Singapore16
FR · France7
PL · Poland1

Network (ASN)

fingerprintco-occurrences
AS211619 · MAXKO d.o.o.639
AS48090 · TECHOFF SRV LIMITED124
AS49870 · Alsycon B.V.91
AS138997 · Eons Data Communications Limited15
AS3320 · Deutsche Telekom AG6
AS197170 · TechTies Inc.5
AS211590 · Bucklog SARL4
AS9009 · M247 Europe SRL3
AS14061 · DigitalOcean, LLC1
AS12876 · Scaleway SAS1

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.643
001d,0017,0018,0019 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13, curl 8.7.1.The fingerprint page shows the full measured match list. More on the catalog.28
0017,0019,0018,001616
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.5
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.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
q13d0312h3_55b375c5d22e_178839b6cec14