---
id: CVE-2026-100409
title: OpenNext Cloudflare is an open Next.js adapter for Cloudflare
summary: >-
  OpenNext Cloudflare is an open Next.js adapter for Cloudflare. From 0.3.0
  until 1.20.2, applications that enable enableCacheInterception, rely on
  middleware for access control, and have a matching cached protected route
  process encoded p…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-177
  - CWE-180
vendor: opennextjs
product: opennextjs-cloudflare
affected:
  - 'opennextjs-cloudflare >= 0.3.0, < 1.20.2'
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T18:17:21.500'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100409'
references:
  - url: 'https://github.com/opennextjs/opennextjs-aws/pull/1199'
    label: security-advisories@github.com
  - url: 'https://github.com/opennextjs/opennextjs-aws/pull/1200'
    label: security-advisories@github.com
  - url: >-
      https://github.com/opennextjs/opennextjs-cloudflare/commit/38ea40b669be272ddf09a7df7e70c69d0b57404b
    label: security-advisories@github.com
  - url: >-
      https://github.com/opennextjs/opennextjs-cloudflare/releases/tag/@opennextjs/cloudflare@1.20.2
    label: security-advisories@github.com
  - url: >-
      https://github.com/opennextjs/opennextjs-cloudflare/security/advisories/GHSA-2vc4-c4r6-p6v6
    label: security-advisories@github.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100409'
  - url: 'https://github.com/advisories/GHSA-2vc4-c4r6-p6v6'
tags:
  - nvd
  - cve.org
  - ghsa
  - npm
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-15T17:50:22.601978Z'
ingestedAt: '2026-10-15T17:18:20.096Z'
aliases:
  - GHSA-2vc4-c4r6-p6v6
ecosystem: npm
patched:
  - '@opennextjs/cloudflare 1.20.2'
---

## Overview

OpenNext Cloudflare is an open Next.js adapter for Cloudflare. From 0.3.0 until 1.20.2, applications that enable enableCacheInterception, rely on middleware for access control, and have a matching cached protected route process encoded pathnames inconsistently between middleware matching and cache lookup. An unauthenticated attacker can use a percent-encoded pathname that does not match authorization middleware but decodes to the cache key of a protected route, causing cached content to be returned without authorization. Malformed encodings can also be partially decoded, allowing cache lookup to continue with a pathname that middleware did not evaluate consistently. This issue is fixed in version 1.20.2.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-100409)

Affected packages:

- `@opennextjs/cloudflare >= 0.3.0, < 1.20.2`

Patched in:

- `@opennextjs/cloudflare 1.20.2`

Source: https://github.com/advisories/GHSA-2vc4-c4r6-p6v6