Kiota Typescript

@microsoft/kiota-http-fetchlibrary provides TypeScript libraries for Kiota-generated API clients. In versions 1.0.0-preview.97 through 1.0.0-preview.101, `@microsoft/kiota-http-fetchlibrary`'s `RedirectHandler` is documented as stripping `Authorization` and `Cookie` from cross-origin redirect targets, but the default `scrubSensitiveHeaders` callback in `RedirectHandlerOptions` uses case-sensitive property deletion (`delete headers.Authorization`, `delete headers.Cookie`) on a headers object that `FetchRequestAdapter.getRequestFromRequestInformation` has already lower-cased. The delete therefore targets keys that do not exist, the scrub is a no-op, and any Bearer token or Cookie attached by a kiota-generated SDK is forwarded to an attacker-controlled host across a 30x redirect. This is reachable in the default middleware chain (`MiddlewareFactory.getDefaultMiddlewares`) with no custom configuration, and applies to every kiota-generated TypeScript SDK that uses `BaseBearerTokenAuthenticationProvider` or any other authentication provider that sets the `Authorization` request header. Version 1.0.0-preview.102 patches the issue.

Published: 2026-06-19T18:19:03.222Z
Updated: 2026-06-22T15:05:46.759Z

The RedirectHandler middleware in microsoft/kiota-java (com.microsoft.kiota:microsoft-kiota-http-okHttp v1.9.0) and other Kiota libraries fails to strip sensitive HTTP headers when following 3xx redirects to a different host or scheme. Only the Authorization header is removed; Cookie, Proxy-Authorization, and all custom headers are forwarded to the redirect target.

Published: 2026-05-14T15:58:57.772Z
Updated: 2026-05-14T19:51:10.682Z