TCP SYN (p0f)

4:50+14:0:1460:mss*29,12:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-06-29 15:42 · last seen 2026-10-23 22:38 · JSON

Distinct clients per day (last 30 days, peak 3/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 TTL50+14
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
t13d191000_9dc949149365_e7c2852226518
t13d1011h2_18ef40b21276_879711aa9f168
t13d251100_b78ed14e2fd0_ab7e3b40a6777
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
t13i1909h2_9dc949149365_97f8aa674fd92
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
t13d190900_9dc949149365_97f8aa674fd91
t13d1515h1_8daaf6152771_0a20fe35d3a51

HTTP request (JA4H)

fingerprintco-occurrences
ge11nn040000_8391bea91fb6_000000000000_0000000000008
ge20nn14enus_068ebe3632ec_000000000000_0000000000006
po11nn080000_4e91bb52a450_000000000000_0000000000004
ge20nn030000_bf75ddd0bb29_000000000000_0000000000003
ge11nr060000_ca2da16acdf9_000000000000_0000000000002
po20nn23enus_91c53b5c6d06_000000000000_0000000000001
po20nn15enus_6175c8d80ef7_000000000000_0000000000001
ge20nr030000_ff50983941c1_000000000000_0000000000001
ge20nr030000_80b089f68b8e_000000000000_0000000000001
ge11nr050000_57c5e92682a8_000000000000_0000000000001

HTTP/2 frames (Akamai)

fingerprintco-occurrences
0|00|0|m,s,a,p8
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
2:0;4:4194304;5:16384;6:10485760|1073741824|0|a,m,p,s Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.26.6, go-net/http 1.26.10, go-net/http 1.26.9, +8 more.The fingerprint page shows the full measured match list. More on the catalog.2

TCP SYN (JA4T)

fingerprintco-occurrences
42340_2-4-8-1-3_1460_1228

User-Agent

fingerprintco-occurrences
curl/8.7.17
curl/8.14.13
Mozilla/5.0 zgrab/0.x2
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.361
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.361
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.361
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.5 Safari/605.1.151
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.2 Safari/605.1.151

Country

fingerprintco-occurrences
NL · Netherlands19
FR · France9
US · United States2
IE · Ireland1

Network (ASN)

fingerprintco-occurrences
AS48090 · TECHOFF SRV LIMITED16
AS211590 · Bucklog SARL8
AS14061 · DigitalOcean, LLC2
AS212238 · Datacamp Limited2
AS9009 · M247 Europe SRL1
AS12876 · Scaleway SAS1
AS218785 · TC DATACENTER 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.3
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.2