CVE-2026-94484: Next Denial of Service Vulnerability

MODERATE
Advisory Identifier: GHSA-mcj8-r9mp-w47p
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CVSS 4.8
CWE-524
Published
Advisory Summary

CVE-2026-94484 is a MODERATE (CVSS 4.8) denial of service vulnerability (CWE-524: Use of Cache Containing Sensitive Information) affecting Next libraries in the npm ecosystem. The issue involves next.js has cache poisoning in ssg/isr rendering that leads to cross-user content substitution and persistent denial of service. Remediation is available by upgrading affected packages to version 16.3.8, 15.5.27.

CVE-2026-94484 at a Glance

CVE Identifier CVE-2026-94484
GHSA Identifier GHSA-mcj8-r9mp-w47p
Severity MODERATE
CVSS v3.1 Base Score 4.8
CWE Classification CWE-524: Use of Cache Containing Sensitive Information
Affected Product Next
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 4.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2026-94484

To remediate this vulnerability, upgrade all affected Next dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

next fixed: 16.3.8 
npm install next@16.3.8
next fixed: 15.5.27 
npm install next@15.5.27
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls next

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-94484, inspect your project dependencies using npm:

npm ls next

Analyze the terminal output to locate any version of Next in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 16.3.8), your application is affected.

Note: The npm ls next command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-524: Use of Cache Containing Sensitive Information, where the code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere. In Next, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

Next.js applications that use a root-level catch-all page together with statically generated or Incremental Static Regeneration routes can have their shared response cache poisoned by a single unauthenticated crafted request.

CVE-2026-94484 Affected Next Versions

2 component(s)
Fixed Versions:
16.3.815.5.27
Product / Package Ecosystem Affected Versions Fixed Version
next
npm/next
npm
≥ 16.0.0
< 16.3.8
16.3.8
next
npm/next
npm
≥ 15.0.0
< 15.5.27
15.5.27

References

GitHub Advisory / Wiki ADVISORY
https://github.com/vercel/next.js/security/advisories/GHSA-mcj8-r9mp-w47p
NVD — CVE-2026-94484 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-94484
Security Fix Commit FIX COMMIT
https://github.com/vercel/next.js/commit/52c94abdd2ea5f416f5e8353ea8a2edd3fe311b8
Security Fix Commit FIX COMMIT
https://github.com/vercel/next.js/commit/719e4c67d6e92df60246f95e1d96e2dd60789a52
Next Source Repository REPOSITORY
https://github.com/vercel/next.js
Next Release RELEASE
https://github.com/vercel/next.js/releases/tag/v15.5.27
Next Release RELEASE
https://github.com/vercel/next.js/releases/tag/v16.3.8

Frequently Asked Questions

What is CVE-2026-94484?
CVE-2026-94484 is a security vulnerability in Next involving Next.js has cache poisoning in SSG/ISR rendering that leads to cross-user content substitution and persistent denial of service under CWE-524: Use of Cache Containing Sensitive Information.
Which Next versions are affected?
Affected versions include releases prior to 16.3.8, 15.5.27 across affected packages: next.
What version fixes CVE-2026-94484?
Upgrading to 16.3.8, 15.5.27 (or the latest patched release for your respective branch) resolves the vulnerability.
Is next affected?
Yes, next is affected in releases prior to 16.3.8, 15.5.27. Upgrade your dependency to 16.3.8, 15.5.27 or later.
What is the CVSS score of CVE-2026-94484?
CVE-2026-94484 has a CVSS v3.1 base score of 4.8 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L.
What CWE is associated with CVE-2026-94484?
CVE-2026-94484 is classified under CWE-524: Use of Cache Containing Sensitive Information (The code uses a cache that contains sensitive information, but the cache can be read by an actor outside of the intended control sphere.).
How can I check npm dependencies for CVE-2026-94484?
Run the dependency tree command: 'npm ls next'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
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  "schema_version" : "1.4.0",
  "id" : "GHSA-mcj8-r9mp-w47p",
  "modified" : "2026-10-07T20:31:14Z",
  "published" : "2026-10-07T20:31:13Z",
  "aliases" : [ "CVE-2026-94484" ],
  "summary" : "Next.js has cache poisoning in SSG/ISR rendering that leads to cross-user content substitution and persistent denial of service",
  "details" : "Next.js applications that use a root-level catch-all page together with statically generated or Incremental Static Regeneration routes can have their shared response cache poisoned by a single unauthenticated crafted request.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
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  } ],
  "references" : [ {
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  "database_specific" : {
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    "github_reviewed_at" : "2026-10-07T20:31:13Z",
    "nvd_published_at" : "2026-10-02T16:16:51Z"
  }
}