GHSA-492v-c6pp-mqqv · Severity: high · Ecosystem: npm — Next.js has a Middleware / Proxy bypass through dynamic route parameter injection
Next.js is a React framework for building full-stack web applications. From 15.4.0 to before 15.5.16 and 16.2.5, applications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check. This vulnerability is fixed in 15.5.16 and 16.2.5.
Conclusion & alert: CVE-2026-44574 is rated Moderate Risk (43.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.38%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.03% | 0.38% | +0.36% |
| 2 | 2026-05-14 | — | 0.03% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.1 | 3.1 | HIGH |
|
2.8 | 5.2 | [email protected] |
GHSA-492v-c6pp-mqqv · Severity: high · Ecosystem: npm — Next.js has a Middleware / Proxy bypass through dynamic route parameter injection
| URL | Tags |
|---|---|
| https://github.com/vercel/next.js/security/advisories/GHSA-492v-c6pp-mqqv | Vendor Advisory |