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TI-2026-36514 Aliases CVE-2026-49336GHSA-396q-4vc8-28x9

Information disclosure in Microsoft kiota-typescript

Priority MEDIUM 64CWE-178Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-200.

Summary

@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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00748 55th percentileScored 2026-11-07
Fix Fixed kiota-typescript (microsoft): 1.0.0-preview.102@microsoft/kiota-http-fetchlibrary (npm): 1.0.0-preview.102

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Microsoftkiota-typescript1.0.0-preview.97 to before 1.0.0-preview.1021.0.0-preview.102Patch availableCNA
—@microsoft/kiota-http-fetchlibrary (npm)1.0.0-preview.97 to before 1.0.0-preview.1021.0.0-preview.102Patch availableGHSA-396q-4vc8-28x9
  • kiota-typescript VendorMicrosoft Affected 1.0.0-preview.97 to before 1.0.0-preview.102 Fixed in 1.0.0-preview.102 Patch available CNA
  • @microsoft/kiota-http-fetchlibrary (npm) Vendor— Affected 1.0.0-preview.97 to before 1.0.0-preview.102 Fixed in 1.0.0-preview.102 Patch available GHSA-396q-4vc8-28x9

Remediation

  • Fix · CNA kiota-typescript (microsoft) Fixed in 1.0.0-preview.102
  • Fix · GHSA-396q-4vc8-28x9 @microsoft/kiota-http-fetchlibrary (npm) Fixed in 1.0.0-preview.102 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49336
  2. 2026-10-03 Alias added: GHSA-396q-4vc8-28x9

References

Advisory 1

Other 3

  • TI-2026-42212 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-37256 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
See all 18045 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences