GHSA-492V-C6PP-MQQV

Vulnerability from github – Published: 2026-05-11 15:54 – Updated: 2026-05-14 20:38
VLAI
Summary
Next.js has a Middleware / Proxy bypass through dynamic route parameter injection
Details

Impact

Applications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check.

Fix

We now only honor internal route-parameter normalization in trusted routing flows and ignore externally supplied parameter encodings that should never have been accepted from ordinary requests.

Workarounds

If you cannot upgrade immediately, enforce authorization in route or page logic instead of relying solely on middleware path matching.

Severity
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "next"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "15.4.0"
            },
            {
              "fixed": "15.5.16"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "next"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "16.0.0"
            },
            {
              "fixed": "16.2.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44574"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-288"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-11T15:54:08Z",
    "nvd_published_at": "2026-05-13T17:16:22Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nApplications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check.\n\n### Fix\n\nWe now only honor internal route-parameter normalization in trusted routing flows and ignore externally supplied parameter encodings that should never have been accepted from ordinary requests.\n\n### Workarounds\n\nIf you cannot upgrade immediately, enforce authorization in route or page logic instead of relying solely on middleware path matching.",
  "id": "GHSA-492v-c6pp-mqqv",
  "modified": "2026-05-14T20:38:03Z",
  "published": "2026-05-11T15:54:08Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/vercel/next.js/security/advisories/GHSA-492v-c6pp-mqqv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-44574"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vercel/next.js"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vercel/next.js/releases/tag/v15.5.16"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vercel/next.js/releases/tag/v16.2.5"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Next.js has a Middleware / Proxy bypass through dynamic route parameter injection"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.