Kludex Starlette HTTP Request/Response Smuggling Vulnerability

What happened

Kludex Starlette contains a HTTP request/response smuggling vulnerability that could allow attackers to inject paths into the host part, prepending the actual path leading to issues such as authentication bypass when the authentication depends on the reconstructed URL’s path. This vulnerability could be chaned with CVE-2026-42271.

Affected versions

Starlette: See original advisory Fixed: See vendor advisory.

Why it matters

This source correlation may provide earlier visibility while structured CVE metadata is still being updated.

Detection & mitigation

• Review the original advisory and validate affected versions.
• Apply vendor-provided updates or mitigations when available.