{"id":"CVE-2026-49336","sourceIdentifier":"security-advisories@github.com","published":"2026-06-19T19:16:36.430","lastModified":"2026-10-25T23:10:00.167","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"@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."},{"lang":"es","value":"@microsoft/kiota-http-fetchlibrary proporciona bibliotecas TypeScript para clientes API generados por Kiota. En las versiones 1.0.0-preview.97 a 1.0.0-preview.101, el ’RedirectHandler’ de ’@microsoft/kiota-http-fetchlibrary’ está documentado como que elimina ’Authorization’ y ’Cookie’ de los destinos de redirección de origen cruzado, pero la devolución de llamada predeterminada ’scrubSensitiveHeaders’ en ’RedirectHandlerOptions’ utiliza la eliminación de propiedades que distingue entre mayúsculas y minúsculas (’delete headers.Authorization’, ’delete headers.Cookie’) en un objeto de encabezados que ’FetchRequestAdapter.getRequestFromRequestInformation’ ya ha convertido a minúsculas. Por lo tanto, la eliminación apunta a claves que no existen, la limpieza es una operación nula, y cualquier token Bearer o cookie adjuntado por un SDK generado por Kiota se reenvía a un host controlado por el atacante a través de una redirección 30x. Esto es accesible en la cadena de middleware predeterminada (’MiddlewareFactory.getDefaultMiddlewares’) sin configuración personalizada, y se aplica a cada SDK TypeScript generado por Kiota que utiliza ’BaseBearerTokenAuthenticationProvider’ o cualquier otro proveedor de autenticación que establece el encabezado de solicitud ’Authorization’. La versión 1.0.0-preview.102 corrige el problema."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"microsoft","product":"kiota-typescript","versions":[{"version":">= 1.0.0-preview.97, < 1.0.0-preview.102","status":"affected"}]}]}],"metrics":{"cvssMetricV40":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"PROOF_OF_CONCEPT","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-22T15:05:06.323889Z","id":"CVE-2026-49336","options":[{"exploitation":"poc"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-178"},{"lang":"en","value":"CWE-200"}]}],"references":[{"url":"https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974","source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9","source":"security-advisories@github.com"},{"url":"https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}