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All fingerprint checksAutomation surface

navigator.webdriver does not assert WebDriver control

Check id webdriver-off

What an ordinary browser yields

true is a finding; false or undefined is unclassified rather than evidence of a human.

What a detector infers

This check is intentionally one-way. The WebDriver specification defines navigator.webdriver as the browser's assertion that it is under remote control, so true is direct evidence. False or undefined is not a pass: launch flags and patched builds can suppress the value, so absence proves nothing and is reported N/A. Descriptor integrity is evaluated separately.

How to resolve it

Launch the browser without the automation flag (--enable-automation and the WebDriver-enabled launch path both set this). Clearcote's engine returns false natively. Do not patch this with a userland Object.defineProperty — the value would read false while the descriptor shape becomes a new contradiction.

Why does navigator.webdriver reveal automation?

Read in the wild by

PerimeterX / HUMAN

Collects navigator.webdriver twice over: once coerced to a string, and separately as its own field recording whether the property exists on navigator at all.

PerimeterX main.min.js (ifood deployment): `function AL(){return hU[AC]+""}` and `function AM(){return AC in hU?1:0}`, where `hU=navigator` and `AC=hQ(512)`, with the script's string table resolving 512 to "webdriver" (hQ_map.json:514). Their results land in the EV2 payload at main.min.js:7710-7711 as `t[hQ(745)]=t["GCQtLl1BLR0="]=AL()` and `t["aRVcHy92XiQ="]=t["QS00ZwRJNFE="]=AM()`; captured payloads carry "GCQtLl1BLR0=": "false" and "QS00ZwRJNFE=": 1 (ev2_template.json:106,108 and all six samples in stample/ifood/sample/*/decoded_payload_2.json).

CreepJS

CreepJS, an open-source research demo rather than a production detector, reads navigator.webdriver directly: its webDriverIsOn flag trips on a truthy value, on its own lie-detector flagging the property, or — behind a CSS feature test — on the property being absent entirely. It is one of three inputs to CreepJS's headless rating.

src/headless/index.ts lines 97-102, inside `headless: { ... }`: `webDriverIsOn: ((CSS.supports('border-end-end-radius: initial') && navigator.webdriver === undefined) || !!navigator.webdriver || !!lieProps['Navigator.webdriver'])` — and line 167: `const headlessRating = +((headlessKeys.filter((key) => headless[key]).length / headlessKeys.length) * 100).toFixed(0)`, where `headless` holds exactly three keys (webDriverIsOn, hasHeadlessUA, hasHeadlessWorkerUA).

Kasada

Reads the automation flag in BOTH realms, because an override installed on the page's navigator does not follow into a fresh iframe.

window_navigator_webdriver, iframe_navigator_webdriver

Kasada ips.js teardown — the full 427-probe list

Every attribution traces to a published artifact. See the sources and their limits.

Nearby checks in Automation surface

See all 27 checks in Automation surface
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 Automation surface 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 Automation surface — the family webdriver-off belongs to.