OpenNext Cloudflare: Cache interception can bypass middleware protection for encoded paths

{
  "id": "d94d2011669e6bfd76c52ca7f886579ce7ab0e821f5889e2ac9ad0f9a7365f5b",
  "url": "https://osv.dev/vulnerability/GHSA-2vc4-c4r6-p6v6",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "OpenNext Cloudflare: Cache interception can bypass middleware protection for encoded paths",
    "summary": "## Summary When cache interception is enabled, `@opennextjs/cloudflare` can interpret percent-encoded paths differently during middleware matching and cache lookup. An encoded request may fail to match authorization middleware, then be decoded into the cache key of a protected route. The cached response may consequently be returned without invoking the middleware. `enableCacheInterception` is disabled by default. ## Impact A remote unauthenticated attacker may retrieve cached content from routes intended to be protected by middleware. An application is affected when it: - explicitly enables `enableCacheInterception`; - relies on middleware for access control; and - has a matching cached route. ## Details Middleware matching previously used the encoded request pathname, while cache interception decoded the pathname before selecting a cache entry. For example, consider an application with: - middleware matcher `/admin/:path*`; - middleware returning `401 Authentication required` for `/admin`; - a statically generated, cached `/admin` route; and - cache interception enabled: ```ts export default defineCloudflareConfig({ incrementalCache: staticAssetsIncrementalCache, enableCacheInterception: true, }); ``` An attacker can request: ```http GET /%61dmin ``` The encoded pathname does not match `/admin/:path*`, so the authorization middleware is not invoked. Cache interception then decodes `%61dmin` to `admin` and may return the cached `/admin` response: ```http HTTP/1.1 200 OK x-ope",
    "evidence": "osv:GHSA-2vc4-c4r6-p6v6",
    "products": [
      {
        "name": {
          "value": "@opennextjs/cloudflare",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.20.2",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "GHSA-2vc4-c4r6-p6v6",
      "aliases": [
        "CVE-2026-100409",
        "GHSA-2vc4-c4r6-p6v6"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0.3.0"
                },
                {
                  "fixed": "1.20.2"
                }
              ]
            }
          ],
          "package": {
            "name": "@opennextjs/cloudflare",
            "purl": "pkg:npm/%40opennextjs/cloudflare",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-2vc4-c4r6-p6v6/GHSA-2vc4-c4r6-p6v6.json"
          }
        }
      ],
      "modified": "2026-10-15T20:30:05.349670038Z",
      "provider": "osv",
      "references": [
        "https://github.com/opennextjs/opennextjs-cloudflare/security/advisories/GHSA-2vc4-c4r6-p6v6",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-100409",
        "https://github.com/opennextjs/opennextjs-aws/pull/1199",
        "https://github.com/opennextjs/opennextjs-aws/pull/1200",
        "https://github.com/opennextjs/opennextjs-cloudflare/commit/38ea40b669be272ddf09a7df7e70c69d0b57404b",
        "https://github.com/opennextjs/opennextjs-cloudflare",
        "https://github.com/opennextjs/opennextjs-cloudflare/releases/tag/@opennextjs/cloudflare@1.20.2"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-177",
          "CWE-180"
        ],
        "severity": "HIGH",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-15T17:17:07Z",
        "github_reviewed_at": "2026-10-15T20:15:17Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-100409",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 336043,
  "published_at": "2026-10-15T20:15:17+00:00"
}