CVE-2025-29927

High PUBLISHED

Authorization Bypass in Next.js Middleware

vercel · next.js

Not yet in CISA KEV

Exploited in the wild PoC available

Recommended Action

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Confidence
High
Exploitation Status
Exploited in the wild
Observed in Sensors
No
Attempts (30d)
Unique Attacker IPs
CISA KEV
Not yet in CISA KEV
CVSS / EPSS
9.1 Critical

At a Glance

Next.js is a React framework for building full-stack web applications. Starting in version 1.11.4 and prior to versions 12.3.5, 13.5.9, 14.2.25, and 15.2.3, it is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware. If patching to a safe version is infeasible, it is recommend that you prevent external user requests which contain the x-middleware-subrequest header from reaching your Next.js application. This vulnerability is fixed in 12.3.5, 13.5.9, 14.2.25, and 15.2.3.

nuclei_scanner
CVE Published
Mar 21, 2025
Exploitation Reported
Jul 02, 2026
CVSS
9.1 Critical
EPSS
Remote Low complexity No user interaction Unauthenticated

Affected Versions

Vendor Product Version Status
vercel
next.js

>= 11.1.4, < 12.3.5

Affected
vercel
next.js

>= 14.0.0, < 14.2.25

Affected
vercel
next.js

>= 15.0.0, < 15.2.3

Affected
vercel
next.js

>= 13.0.0, < 13.5.9

Affected

CVE References

Recommended Actions

  • Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
  • Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
  • Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.