TCP SYN (p0f)
4:48+16:0:1340:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df,ecn:0
first seen 2026-10-05 20:02 · last seen 2026-10-05 20:02 · 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 version | 4 |
|---|---|
| Initial TTL | 48+16 |
| Options length | 0 |
| MSS | 1340 |
| Window size | 65535 |
| Window scale | 6 |
| Options layout | mss,nop,ws,nop,nop,ts,sok,eol+1 |
| Quirks | df,ecn |
| Payload class | 0 |
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)
| fingerprint | co-occurrences |
|---|---|
t13d1517h2_8daaf6152771_3cbfd9057e0d Match?Exact match in Thumbprint's published controlled catalog captures: firefox 155.0.1, firefox 154.0, firefox 156.0, +7 more.The fingerprint page shows the full measured match list. More on the catalog. | 24 |
HTTP request (JA4H)
| fingerprint | co-occurrences |
|---|---|
ge20nr11enus_3901d4197baf_000000000000_000000000000 | 20 |
ge20nr10enus_b3034183f430_000000000000_000000000000 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. | 4 |
HTTP/2 frames (Akamai)
| fingerprint | co-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, +31 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, +12 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|17:0:0:42|m,p,a,s | 1 |
1:65536;2:0;4:131072;5:16384|12517377|13:0:0:42|m,p,a,s | 1 |
1:65536;2:0;4:131072;5:16384|12517377|15:0:0:42|m,p,a,s | 1 |
1:65536;2:0;4:131072;5:16384|12517377|19:0:0:42|m,p,a,s | 1 |
1:65536;2:0;4:131072;5:16384|12517377|21:0:0:42|m,p,a,s | 1 |
1:65536;2:0;4:131072;5:16384|12517377|25:0:0:42|m,p,a,s | 1 |
TCP SYN (JA4T)
| fingerprint | co-occurrences |
|---|---|
65535_2-1-3-1-1-8-4-0-0_1340_6 | 24 |
User-Agent
| fingerprint | co-occurrences |
|---|---|
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:156.0) Gecko/20100101 Firefox/156.0 | 24 |
Country
| fingerprint | co-occurrences |
|---|---|
DE · Germany | 24 |
Network (ASN)
| fingerprint | co-occurrences |
|---|---|
AS43357 · Owl Limited | 24 |