JA4 q13d0313h3_55b375c5d22e_e08d512f6d51

q13d0313h3_55b375c5d22e_e08d512f6d51

Firefox — inferred from the User-Agent on its requests.

What this fingerprint encodes

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

• extended_master_secret
• record_size_limit
• application_layer_protocol_negotiation
• 34 (0x0022)
• status_request
• signature_algorithms
• supported_versions
• key_share
• renegotiation_info
• server_name
• supported_groups
• quic_transport_parameters
• encrypted_client_hello

Named groups 5

• SecP256r1MLKEM768
• x25519
• secp256r1
• secp384r1
• secp521r1

771,4865-4867-4866,23-28-16-34-5-13-43-51-65281-0-10-57-65037,4588-29-23-24-25,

Seen in live traffic

Connections

7

First seen

2026-09-18 20:13 UTC

Last seen

2026-09-18 20:23 UTC

Transport

QUIC

JA3 hashes absorbed

7

The same client, 7 different JA3s

This one JA4 covers 7 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 7 unrelated clients. JA4 sorts those lists before hashing, which is why all of it lands here instead.

• be2ca4339ea240a600fff8b173399680
• a0328f03f93fd2edd66c20208d1c9e56
• 42a3b5d42be8815f85f14c9df2711f96
• 2d7c565fb4b585a722176c7ed42d79bd
• 0550a1098e4944d3fa448c2eead8bce6
• 40d1e9b6128019d51970c09f2ff0932b
• d1fb7b5faa5917774d04ebcfd347fb53

User-Agents seen on this fingerprint

• Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.0 62×

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.