Next.js is a React framework for building full-stack web applications. To mitigate CVE-2025-29927, Next.js validated the x-middleware-subrequest-id which persisted across multiple incoming requests. However, this subrequest ID is sent to all requests, even if the destination is not the same host as the Next.js application. Initiating a fetch request to a third-party within Middleware will send the x-middleware-subrequest-id to that third party. This vulnerability is fixed in 12.3.6, 13.5.10, 14.2.26, and 15.2.4.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 10 Sep 2025 15:15:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:vercel:next.js:12.3.5:*:*:*:*:node.js:*:*
cpe:2.3:a:vercel:next.js:13.5.9:*:*:*:*:node.js:*:*
cpe:2.3:a:vercel:next.js:14.2.25:*:*:*:*:node.js:*:*
cpe:2.3:a:vercel:next.js:15.2.3:*:*:*:*:node.js:*:*
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}

cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'}


Fri, 11 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00063}

epss

{'score': 0.00067}


Fri, 04 Apr 2025 02:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}

threat_severity

Low


Thu, 03 Apr 2025 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 02 Apr 2025 21:30:00 +0000

Type Values Removed Values Added
Description Next.js is a React framework for building full-stack web applications. To mitigate CVE-2025-29927, Next.js validated the x-middleware-subrequest-id which persisted across multiple incoming requests. However, this subrequest ID is sent to all requests, even if the destination is not the same host as the Next.js application. Initiating a fetch request to a third-party within Middleware will send the x-middleware-subrequest-id to that third party. This vulnerability is fixed in 12.3.6, 13.5.10, 14.2.26, and 15.2.4.
Title Next.js may leak x-middleware-subrequest-id to external hosts
Weaknesses CWE-200
References
Metrics cvssV4_0

{'score': 1.7, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-04-03T13:44:11.988Z

Reserved: 2025-03-18T18:15:13.850Z

Link: CVE-2025-30218

cve-icon Vulnrichment

Updated: 2025-04-03T13:44:06.596Z

cve-icon NVD

Status : Analyzed

Published: 2025-04-02T22:15:19.940

Modified: 2025-09-10T15:14:08.560

Link: CVE-2025-30218

cve-icon Redhat

Severity : Low

Publid Date: 2025-04-02T21:23:14Z

Links: CVE-2025-30218 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-12T15:26:05Z