User-Agent

Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:155.0) Gecko/20100101 Firefox/155.0

first seen 2026-09-15 07:20 · last seen 2026-10-02 14:33 · 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

Browser / clientFirefox 155.0
Operating systemLinux x86_64
Device classdesktop
Noteinferred from the self-declared string — a claim, not a measurement; compare with the wire fingerprints above

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
q13d0315h3_55b375c5d22e_dc5437974b47 Match?Exact match in Thumbprint's published controlled catalog captures: firefox 153.0, firefox 153.0.3, firefox 155.0.1, +27 more.The fingerprint page shows the full measured match list. More on the catalog.20
t13d1516h2_8daaf6152771_0c27189014cf Match?Exact match in Thumbprint's published controlled catalog captures: firefox 154.0, firefox 155.0.1, firefox 155.0, +6 more.The fingerprint page shows the full measured match list. More on the catalog.4
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.4

HTTP request (JA4H)

fingerprintco-occurrences
ge30nr10enus_23a803442ffa_000000000000_0000000000008
ge20nr11enus_1d88e8a431b9_000000000000_0000000000006
ge30nr10enus_432609af9ecc_000000000000_0000000000004
ge30nr11enus_afd16bc40968_000000000000_0000000000004
ge30nr12enus_57c544194b26_000000000000_0000000000003
ge30nr11enus_0c72cb6d0dd2_000000000000_0000000000001
ge20nr12enus_b072defda72f_000000000000_0000000000001
ge20nr11enus_0f34dad662af_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 155.0.1, +32 more.The fingerprint page shows the full measured match list. More on the catalog.4
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, +13 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 158.0.1, firefox 155.0, +4 more.The fingerprint page shows the full measured match list. More on the catalog.1

TCP SYN (p0f)

fingerprintco-occurrences
4:50+14:0:1452:mss*45,7:mss,sok,ts,nop,ws:df,id+:07
4:50+14:0:1452:mss*44,7:mss,sok,ts,nop,ws:df,id+:01

TCP SYN (JA4T)

fingerprintco-occurrences
65340_2-4-8-1-3_1452_77
64240_2-4-8-1-3_1452_71

QUIC transport params

fingerprintco-occurrences
q13_c3e7031b10dc Match?Exact match in Thumbprint's published controlled catalog captures: firefox 155.0.1, firefox 156.0, firefox 158.0.1, +6 more.The fingerprint page shows the full measured match list. More on the catalog.20

Country

fingerprintco-occurrences
ES · Spain28

Network (ASN)

fingerprintco-occurrences
AS3352 · TELEFONICA DE ESPANA S.A.U.28

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
q13d0315h3_55b375c5d22e_dc5437974b474
t13d1516h2_8daaf6152771_0c27189014cf2
t13d1517h2_8daaf6152771_3cbfd9057e0d2