CVE-2026-85152: undici vulnerable to cross-origin cache poisoning via missing origin isolation in interceptors

## Impact When `interceptors.cache()` or `interceptors.deduplicate()` is used with a dispatcher that does not carry a single authoritative origin, or when a request supplies its own `origin`, undici builds the cache and deduplication keys without the actual destination origin. If a cache store or interceptor instance is shared across more than one origin, otherwise-identical requests to different origins are keyed together. An attacker who controls the response from one origin can then have that response returned for a request to a different, trusted origin when the method, path, and relevant headers match. This allows cross-origin information disclosure and persistent cache poisoning, including chains such as JWKS cache poisoning where a token signed with an attacker-held key is accepted as belonging to a trusted issuer. Applications that share `interceptors.cache()` or `interceptors.deduplicate()` state across origins are affected. An `Agent` is not affected, because its dispatch options include the request origin. This was introduced in undici 8.10.0 and affects 8.10.0 and 8.10.1. ## Patches Upgrade to undici v8.10.2. ## Workarounds Use a separate cache store and a separate interceptor instance for each origin, and do not share them across origins.