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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-48710 Detail

Description

Starlette is a lightweight ASGI framework/toolkit. Prior to version 1.0.1, the HTTP `Host` request header was not validated before being used to reconstruct `request.url`. Because the routing algorithm relies on the raw HTTP path while `request.url` is rebuilt from the `Host` header, a malformed header could make `request.url.path` differ from the path that was actually requested. Middleware and endpoints that apply security restrictions based on `request.url` (rather than the raw `scope` path) could therefore be bypassed. Users should upgrade to a version greater than or equal to version 1.0.1, which validates the `Host` header against the grammar of RFC 9112 §3.2 / RFC 3986 §3.2.2 when constructing `request.url` and falls back to `scope["server"]` for malformed values.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://badhost.org GitHub, Inc.
https://github.com/Kludex/starlette/commit/764dab0dcfb9033d75442d7a359645c9f94648c6 GitHub, Inc.
https://github.com/Kludex/starlette/security/advisories/GHSA-86qp-5c8j-p5mr GitHub, Inc.
https://github.com/pypa/advisory-database/tree/main/vulns/starlette/PYSEC-2026-161.yaml GitHub, Inc.
https://ostif.org/disclosing-the-badhost-vulnerability-in-starlette GitHub, Inc.
https://www.secwest.net/starlette GitHub, Inc.
https://www.x41-dsec.de/lab/advisories/x41-2026-002-starlette GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-48710
NVD Published Date:
05/26/2026
NVD Last Modified:
05/26/2026
Source:
GitHub, Inc.