TCP SYN (p0f)

4:51+13:0:1452:mss*44,10:mss,sok,ts,nop,ws:df,id+:0

first seen 2026-07-06 10:27 · last seen 2026-09-03 19:17 · JSON

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
MSS1452
Window sizemss*44
Window scale10
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
t13d1617h2_86a278354501_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.3, +10 more.The fingerprint page shows the full measured match list. More on the catalog.7
t13d1616h2_86a278354501_0c27189014cf Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 152.0.6, +10 more.The fingerprint page shows the full measured match list. More on the catalog.1
t13d3113h1_e8f1e7e78f70_d339722ba4af1
t13d301100_1d37bd780c83_8e6e362c5eac1

HTTP request (JA4H)

fingerprintco-occurrences
ge20nn11enus_3901d4197baf_000000000000_000000000000 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 152.0.5, firefox 153.0.1, +3 more.The fingerprint page shows the full measured match list. More on the catalog.4
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
ge11nn050000_f42f60d0fe7d_000000000000_0000000000001
he11nn020000_e1391afd0c9d_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.2
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
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
64240_2-4-8-1-3_1452_1010

User-Agent

fingerprintco-occurrences
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.06
Mozilla/5.0 (X11; Linux x86_64; rv:151.0) Gecko/20100101 Firefox/151.02
fingerprint-security-thumbprint-probe/1.01

Country

fingerprintco-occurrences
VN · Vietnam7
ES · Spain2
MA · Morocco1

Network (ASN)

fingerprintco-occurrences
AS18403 · FPT Telecom Company7
AS3352 · TELEFONICA DE ESPANA S.A.U.2
AS36903 · Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM1