5.9

CVE-2025-30218: vercel next.js

CVSS: 5.9v3.1MediumAnalyzed
AliasesGHSA-223j-4rm8-mrmf
Published 02-04-2025Last modified 13-10-2025
Open JSON

Vulnerability summary

CVE-2025-30218 is a medium (CVSS 5.9) vulnerability in vercel next.js. EPSS estimates a 0.42% chance of exploitation in the next 30 days, higher than 35.2% of scored vulnerabilities.

Overall risk
24/100
0100
Low · default modelHow is this calculated?
CVSS score
5.9/10
010
Medium · v3.1 (NVD)
EPSS score
0.42%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 02-04-2025
    PublishedVulnerability first disclosed.
  2. 13-10-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.42%

Chance of exploitation in the next 30 days

Percentile

35%

Versus all other CVEs

30-day change

+0.01 pp

From 0.42% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.42%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Npm1 product
  • next≥ 12.3.5, < 12.3.6 | ≥ 13.5.9, < 13.5.10 | ≥ 14.2.25, < 14.2.26 | ≥ 15.2.3, < 15.2.4
Vercel1 product
  • next.js= 12.3.5 | = 13.5.9 | = 14.2.25 | = 15.2.3 | 12.3.5 | 13.5.9 | 14.2.25 | 15.2.3

2 vendors · 2 products

References

4 links