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All fingerprint checksNetwork & WebRTC

every server-reflexive candidate has a host candidate behind it

Check id webrtc-srflx-without-host

What an ordinary browser yields

Either no reflexive candidate at all, or reflexive candidates accompanied by at least one host candidate (contextual, never scored).

What a detector infers

A server-reflexive candidate is not an address the browser knows about itself. It is what a STUN server reported seeing when a LOCAL socket sent it a packet, which makes it derived from a host candidate by construction. So reflexive entries with no host candidate behind them -- no mDNS .local name, no literal LAN address -- describe the mapping of something that was never gathered. That is the shape most findings on this page share: a value rewritten while the fact derived from it was not recomputed. Substituting a public address into the candidate list is easy; manufacturing the host candidates it would have had to be reflected from is the part that gets skipped. Measured on the reference machine: stock Chrome 150 gathers four candidates, two mDNS host and two server-reflexive, and never reflexive alone. A stealth build configured to report a fixed public address produced seven reflexive candidates all carrying that one address, zero host candidates, and gathering that never reached completion. The row is placed outside the completed-gathering branch for that reason -- inside it, it would be dead code in exactly the case it exists for.

How to resolve it

A reflexive candidate is derived from a host candidate rather than reported independently, so a candidate list cannot hold the reflection without the original. To keep a real public address off the media path, either suppress WebRTC outright or leave mDNS host candidates in place -- both are coherent. Substituting an address into the reflexive entries while the host candidates it would have been reflected from are absent is not.

What is a WebRTC IP leak?

Nearby checks in Network & WebRTC

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Who builds this test

Clearcote is a browser built for fingerprint coherence

It is a Chromium fork, maintained by the same people who wrote this reference. It ships as a compiled browser rather than as a stealth script injected into someone else's — which is a description of how it is built, and is not an argument about how it behaves on this check.

This audit takes no position on how Clearcote scores on Network & WebRTC checks, on this one, or anywhere else. It has no baseline corpus of other people's fingerprints to rank you against and no vendor scoreboard — nearly every check is self-referential, asking one browser the same question through two independent APIs and reporting whether both answers can be true at once. It runs identically on any browser, including ours. Run it on yours and read the result yourself.

See the other checks in Network & WebRTC — the family webrtc-srflx-without-host belongs to.