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CVE-2026-48061

CVE-2026-48061 · Litestar: AllowedHostsMiddleware bypasses host validation via client-controlled X-Forwarded-Host header

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. In versions prior to 2.22.0, an attacker can bypass the allowed hosts validation by omitting the Host header and supplying an X-Forwarded-Host header set to a whitelisted domain. The AllowedHostsMiddleware trusts the X-Forwarded-Host header as a fallback when the Host header is absent. Since X-Forwarded-Host is a client-controllable header, this enables host header injection attacks such as password reset poisoning, cache poisoning, and server-side request routing manipulation. Any application using AllowedHostsConfig is affected when deployed without a reverse proxy that strips X-Forwarded-Host, or when accepting HTTP/1.0 connections. This issue has been fixed in version 2.22.0.

CVSS 5.9 · Medium · EPSS 0.4% · Fix available

Published
Updated

Stack: python

Affected products and versions

  • litestar

    Versions
    • < 2.22.0: Affected

    No fix published

  • litestar PyPI

    Versions
    • 1.0.0a0
    • 2.0.0
    • 2.0.0a3
    • 2.0.0a4
    • 2.0.0a5
    • 2.0.0a6
    • 2.0.0a7
    • 2.0.0b1
    • 2.0.0b2
    • 2.0.0b3
    • 2.0.0b4
    • 2.0.0rc1
    • 2.0.1
    • 2.1.0
    • 2.1.1
    • 2.10.0
    • 2.11.0
    • 2.12.0
    • 2.12.1
    • 2.13.0
    • 2.14.0
    • 2.15.0
    • 2.15.1
    • 2.15.2
    • 2.16.0
    • 2.17.0
    • 2.18.0
    • 2.19.0
    • 2.2.0
    • 2.2.1
    • 2.20.0
    • 2.21.0
    • 2.21.1
    • 2.3.0
    • 2.3.1
    • 2.3.2
    • 2.4.0
    • 2.4.1
    • 2.4.2
    • 2.4.3
    • 2.4.4
    • 2.4.5
    • 2.5.0
    • 2.5.1
    • 2.5.2
    • 2.5.3
    • 2.5.4
    • 2.5.5
    • 2.6.0
    • 2.6.1
    • 2.6.2
    • 2.6.3
    • 2.6.4
    • 2.7.0
    • 2.7.1
    • 2.7.2
    • 2.8.0
    • 2.8.1
    • 2.8.2
    • 2.8.3
    • 2.9.0
    • 2.9.1
    Affected ranges
    • ECOSYSTEM: < 2.22.0

    Update to 2.22.0

Original sources

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