vercel next.js 12.3.5/13.5.9/14.2.25/15.2.3 x-middleware-subrequest-id information disclosure

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in vercel next.js 12.3.5/13.5.9/14.2.25/15.2.3. Affected by this issue is some unknown functionality. The manipulation of the argument x-middleware-subrequest-id results in information disclosure. This vulnerability is cataloged as CVE-2025-30218. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic has been found in vercel next.js 12.3.5/13.5.9/14.2.25/15.2.3. Affected is an unknown code block. The manipulation of the argument x-middleware-subrequest-id with an unknown input leads to a information disclosure vulnerability. CWE is classifying the issue as CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. This is going to have an impact on confidentiality. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2025-30218 since 03/18/2025. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1592.

Upgrading eliminates this vulnerability. The upgrade is hosted for download at vercel.com.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔍
CNA CVSS-BT Score: 🔍
CNA Vector: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: vercel.com

Timelineinfo

03/18/2025 🔍
04/03/2025 +15 days 🔍
04/03/2025 +0 days 🔍
09/10/2025 +160 days 🔍

Sourcesinfo

Product: github.com

Advisory: GHSA-223j-4rm8-mrmf
Status: Confirmed

CVE: CVE-2025-30218 (🔍)
GCVE (CVE): GCVE-0-2025-30218
GCVE (VulDB): GCVE-100-303084

Entryinfo

Created: 04/03/2025 07:31
Updated: 09/10/2025 17:21
Changes: 04/03/2025 07:31 (70), 09/10/2025 17:21 (13)
Complete: 🔍
Cache ID: 216::103

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