TCP SYN (p0f)

4:51+13:0:1260:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df:0

first seen 2026-09-13 01:37 · last seen 2026-09-13 01:37 · JSON

Last 7 days (5 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 version4
Initial TTL51+13
Options length0
MSS1260
Window size65535
Window scale6
Options layoutmss,nop,ws,nop,nop,ts,sok,eol+1
Quirksdf
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
t13d1911h2_9dc949149365_e7c285222651 Match?Exact match in Thumbprint's published controlled catalog captures: go-net/http 1.21.13.The fingerprint page shows the full measured match list. More on the catalog.5

HTTP request (JA4H)

fingerprintco-occurrences
ge20nr10enus_b3034183f430_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 154.0, +21 more.The fingerprint page shows the full measured match list. More on the catalog.4
ge20nr10enus_d353d425b0bb_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.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.1
1:65536;2:0;4:131072;5:16384|12517377|5:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0.3, firefox 154.0, firefox 153.0, +8 more.The fingerprint page shows the full measured match list. More on the catalog.1
1:65536;2:0;4:131072;5:16384|12517377|7:0:0:22|m,p,a,s Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0.3, firefox 155.0, firefox 154.0, +3 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (JA4T)

fingerprintco-occurrences
65535_2-1-3-1-1-8-4-0-0_1260_65

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:155.0) Gecko/20100101 Firefox/155.05

Country

fingerprintco-occurrences
AU · Australia5

Network (ASN)

fingerprintco-occurrences
AS4826 · Vocus Connect International Backbone5