q13d0313h3_55b375c5d22e_fc7519ff7bc2
Firefox — inferred from the User-Agent on its requests.
What this fingerprint encodes
q13d0313h3
handshake shape, human-readable
55b375c5d22e
truncated hash of the cipher list
fc7519ff7bc2
truncated hash of extensions + signature algorithms
- Transport
- QUIC
- TLS version
- TLS 1.3
- Server name
- server name sent
- Cipher suites offered
- 3
- Extensions offered
- 13
- ALPN
- h3
The hello it was computed from
Recovered because the proxy now stores the pre-hash JA3 string alongside the digest. Every number below came out of this client's ClientHello; anything we cannot name in the IANA registry is shown as its raw value rather than guessed at.
- Version
- TLS 1.2
Cipher suites 3
-
TLS_AES_128_GCM_SHA256 -
TLS_CHACHA20_POLY1305_SHA256 -
TLS_AES_256_GCM_SHA384
Extensions 13
-
supported_groups -
renegotiation_info -
supported_versions -
34 (0x0022) -
extended_master_secret -
application_layer_protocol_negotiation -
record_size_limit -
key_share -
server_name -
status_request -
signature_algorithms -
quic_transport_parameters -
encrypted_client_hello
Named groups 5
-
SecP256r1MLKEM768 -
x25519 -
secp256r1 -
secp384r1 -
secp521r1
Raw JA3 string
771,4865-4867-4866,10-65281-43-34-23-16-28-51-0-5-13-57-65037,4588-29-23-24-25,Seen in live traffic
- Connections
- 20
- First seen
- 2026-09-18 20:13 UTC
- Last seen
- 2026-10-05 13:43 UTC
- Transport
- QUIC
- JA3 hashes absorbed
- 20
The same client, 20 different JA3s
This one JA4 covers 20 distinct JA3 hashes. A JA3 hashes the cipher and extension lists in the order they arrived, so a client that shuffles them — which Chrome and its derivatives do on purpose — produces a new JA3 almost every connection and fragments into what looks like 20 unrelated clients. JA4 sorts those lists before hashing, which is why all of it lands here instead.
b42c397e3bb69d33777a26af5f98226f127ec8dacb40e8c419c90a670033921f0550a1098e4944d3fa448c2eead8bce658412b80bc0f036d724d4d74f66113b8af98a172935c7c98cbfa3fea312c01768f08dfb6d7e69850b5e85c3f9af7898028a62590709824a21fcae694f4151d411ad994860dd1373904e7a295c0a1cf11a0328f03f93fd2edd66c20208d1c9e56d1fb7b5faa5917774d04ebcfd347fb53b377ded32b1df94ad7b2fb01921894d742a3b5d42be8815f85f14c9df2711f96- … and 8 more
User-Agents seen on this fingerprint
Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.0101×Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.036×
A User-Agent is self-declared and trivially forged, so this names an observation rather than proving an identity. It is still the strongest signal available: the fingerprint comes off the TLS handshake and the User-Agent off the request that followed, and one client build keeping a stable JA4 while changing what it calls itself is a finding in its own right.
This entry is an observation, not a policy decision. It is here because the edge saw it, not because anyone reviewed it, and it blocks nothing on its own. Only the curated tier drives classification and banning.