{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.0.1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "764dab0dcfb9033d75442d7a359645c9f94648c6"
            }
          ],
          "repo": "https://github.com/kludex/starlette",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-86qp-5c8j-p5mr"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-444"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48710.json"
  },
  "details": "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.",
  "id": "CVE-2026-48710",
  "modified": "2026-07-16T03:31:11.951680283Z",
  "published": "2026-05-26T21:54:54.393Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://badhost.org"
    },
    {
      "type": "WEB",
      "url": "https://ostif.org/disclosing-the-badhost-vulnerability-in-starlette"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48710.json"
    },
    {
      "type": "WEB",
      "url": "https://www.secwest.net/starlette"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:22992"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:22993"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:23346"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:24866"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:26226"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:30088"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:30089"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:34456"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:34526"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:34532"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:37275"
    },
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/security/cve/CVE-2026-48710"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/48xxx/CVE-2026-48710.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/Kludex/starlette/security/advisories/GHSA-86qp-5c8j-p5mr"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/starlette/PYSEC-2026-161.yaml"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-48710"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.x41-dsec.de/lab/advisories/x41-2026-002-starlette"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2481742"
    },
    {
      "type": "FIX",
      "url": "https://github.com/Kludex/starlette/commit/764dab0dcfb9033d75442d7a359645c9f94648c6"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Starlette has missing Host header validation that poisons request.url.path, bypassing path-based security checks"
}