JA4 t13d0313h2_55b375c5d22e_7f2aabb58f9e

t13d0313h2_55b375c5d22e_7f2aabb58f9e

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

What this fingerprint encodes

Transport

TCP

TLS version

TLS 1.3

Server name

server name sent

Cipher suites offered

3

Extensions offered

13

ALPN

h2

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

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

Named groups 6

• x25519
• secp256r1
• secp384r1
• secp521r1
• ffdhe2048
• ffdhe3072

771,4865-4867-4866,0-23-65281-10-16-5-34-18-51-43-13-28-65037,29-23-24-25-256-257,

Seen in live traffic

Connections

6

First seen

2026-10-01 08:16 UTC

Last seen

2026-10-01 08:16 UTC

Transport

TCP

User-Agents seen on this fingerprint

• Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0 1×

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.