PT-2026-51008 · Microsoft · Kiota-Typescript

Tonghuaroot · Published 2026-06-19 · Updated 2026-06-19 · CVE-2026-49336

Positive Technologies (AI Summary)

CVSS v4.0

6.9

Medium

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Name of the Vulnerable Software and Affected Versions @microsoft/kiota-http-fetchlibrary versions 1.0.0-preview.97 through 1.0.0-preview.101

Description The RedirectHandler in the library fails to properly remove sensitive headers during cross-origin redirects. While it is intended to strip Authorization and Cookie headers, the default scrubSensitiveHeaders callback in RedirectHandlerOptions performs case-sensitive deletion. Because the FetchRequestAdapter.getRequestFromRequestInformation function has already converted headers to lowercase, the deletion attempts target non-existent keys. Consequently, the scrubbing process is ineffective, allowing Bearer tokens or Cookies to be forwarded to attacker-controlled hosts during a 30x redirect. This issue affects the default middleware chain (MiddlewareFactory.getDefaultMiddlewares) and any TypeScript SDK using BaseBearerTokenAuthenticationProvider or other providers that set the Authorization header.

Recommendations Update to version 1.0.0-preview.102.

Fix

Information Disclosure

Weakness Enumeration

CWE-200

CWE-178

Related Identifiers

CVE-2026-49336

Affected Products

Kiota-Typescript

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-49336 · Security Note
• https://github.com/microsoft/kiota-typescript/commit/09f8bd9b34d68bf412a9b78f6ca7e7961ef14974 · Note
• https://github.com/microsoft/kiota-typescript/security/advisories/GHSA-396q-4vc8-28x9 · Note
• https://twitter.com/VulmonFeeds/status/2068067943796109365 · Twitter Post