CVE-2025-29927: Next Authorization Bypass Vulnerability

CRITICAL
Advisory Identifier: GHSA-f82v-jwr5-mffw
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CVSS 9.1
CWE-285 CWE-863
Published
Advisory Summary

CVE-2025-29927 is a CRITICAL (CVSS 9.1) authorization bypass vulnerability (CWE-285: Improper Authorization) affecting Next libraries in the npm ecosystem. The issue involves authorization bypass in next.js middleware. Remediation is available by upgrading affected packages to version 13.5.9, 14.2.25, 15.2.3, 12.3.5.

CVE-2025-29927 at a Glance

CVE Identifier CVE-2025-29927
GHSA Identifier GHSA-f82v-jwr5-mffw
Severity CRITICAL
CVSS v3.1 Base Score 9.1
CWE Classification CWE-285: Improper Authorization
Affected Product Next
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 9.1

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

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

How to Fix CVE-2025-29927

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: 13.5.9 
npm install next@13.5.9
next fixed: 14.2.25 
npm install next@14.2.25
next fixed: 15.2.3 
npm install next@15.2.3
next fixed: 12.3.5 
npm install next@12.3.5
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-2025-29927, 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 13.5.9), 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-285: Improper Authorization, where the product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. 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

# Impact It is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware. # Patches * For Next.js 15.x, this issue is fixed in `15.2.3` * For Next.js 14.x, this issue is fixed in `14.2.25` * For Next.js 13.x, this issue is fixed in 13.5.9 * For Next.js 12.x, this issue is fixed in 12.3.5 * For Next.js 11.x, consult the below workaround. _Note: Next.js deployments hosted on Vercel are automatically protected against this vulnerability._ # Workaround If patching to a safe version is infeasible, we recommend that you prevent external user requests which contain the `x-middleware-subrequest` header from reaching your Next.js application. ## Credits - Allam Rachid (zhero;) - Allam Yasser (inzo_)

CVE-2025-29927 Affected Next Versions

4 component(s)
Fixed Versions:
13.5.914.2.2515.2.312.3.5
Product / Package Ecosystem Affected Versions Fixed Version
next
npm/next
npm
≥ 13.0.0
< 13.5.9
13.5.9
next
npm/next
npm
≥ 14.0.0
< 14.2.25
14.2.25
next
npm/next
npm
≥ 15.0.0
< 15.2.3
15.2.3
next
npm/next
npm
≥ 12.0.0
< 12.3.5
12.3.5

References

GitHub Advisory / Wiki ADVISORY
https://github.com/vercel/next.js/security/advisories/GHSA-f82v-jwr5-mffw
NVD — CVE-2025-29927 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-29927
Security Fix Commit FIX COMMIT
https://github.com/vercel/next.js/commit/52a078da3884efe6501613c7834a3d02a91676d2
Security Fix Commit FIX COMMIT
https://github.com/vercel/next.js/commit/5fd3ae8f8542677c6294f32d18022731eab6fe48
Next Source Repository REPOSITORY
https://github.com/vercel/next.js
Next Release RELEASE
https://github.com/vercel/next.js/releases/tag/v12.3.5
Next Release RELEASE
https://github.com/vercel/next.js/releases/tag/v13.5.9
Next Security Information SECURITY
https://security.netapp.com/advisory/ntap-20250328-0002
vercel.com/changelog/vercel-fi... WEB
https://vercel.com/changelog/vercel-firewall-proactively-protects-against-vulnerability-with-middleware
Next Security Information SECURITY
http://www.openwall.com/lists/oss-security/2025/03/23/3
Next Security Information SECURITY
http://www.openwall.com/lists/oss-security/2025/03/23/4

Frequently Asked Questions

What is CVE-2025-29927?
CVE-2025-29927 is a security vulnerability in Next involving Authorization Bypass in Next.js Middleware under CWE-285: Improper Authorization.
Which Next versions are affected?
Affected versions include releases prior to 13.5.9, 14.2.25, 15.2.3, 12.3.5 across affected packages: next.
What version fixes CVE-2025-29927?
Upgrading to 13.5.9, 14.2.25, 15.2.3, 12.3.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is next affected?
Yes, next is affected in releases prior to 13.5.9, 14.2.25, 15.2.3, 12.3.5. Upgrade your dependency to 13.5.9, 14.2.25, 15.2.3, 12.3.5 or later.
What is the CVSS score of CVE-2025-29927?
CVE-2025-29927 has a CVSS v3.1 base score of 9.1 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2025-29927?
CVE-2025-29927 is classified under CWE-285: Improper Authorization (The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.).
How can I check npm dependencies for CVE-2025-29927?
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 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f82v-jwr5-mffw",
  "modified" : "2026-03-02T16:59:03Z",
  "published" : "2025-03-21T15:20:12Z",
  "aliases" : [ "CVE-2025-29927" ],
  "summary" : "Authorization Bypass in Next.js Middleware",
  "details" : "# Impact\nIt is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware.\n\n# Patches\n* For Next.js 15.x, this issue is fixed in `15.2.3`\n* For Next.js 14.x, this issue is fixed in `14.2.25`\n* For Next.js 13.x, this issue is fixed in 13.5.9\n* For Next.js 12.x, this issue is fixed in 12.3.5\n* For Next.js 11.x, consult the below workaround.\n\n_Note: Next.js deployments hosted on Vercel are automatically protected against this vulnerability._\n\n# Workaround\nIf patching to a safe version is infeasible, we recommend that you prevent external user requests which contain the `x-middleware-subrequest` header from reaching your Next.js application.\n\n## Credits\n\n- Allam Rachid (zhero;)\n- Allam Yasser (inzo_)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
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    } ]
  } ],
  "references" : [ {
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    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-29927"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/vercel/next.js/commit/52a078da3884efe6501613c7834a3d02a91676d2"
  }, {
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    "url" : "https://github.com/vercel/next.js/commit/5fd3ae8f8542677c6294f32d18022731eab6fe48"
  }, {
    "type" : "PACKAGE",
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    "url" : "http://www.openwall.com/lists/oss-security/2025/03/23/3"
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    "type" : "WEB",
    "url" : "http://www.openwall.com/lists/oss-security/2025/03/23/4"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-285", "CWE-863" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-03-21T15:20:12Z",
    "nvd_published_at" : "2025-03-21T15:15:42Z"
  }
}