CVE-2026-44574
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.64%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 8.1 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 0.64% probability · 49th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-288, CWE-551
- Affected
- vercel/next.js
- Source
- security-advisories@github.com
References
- https://github.com/vercel/next.js/security/advisories/GHSA-492v-c6pp-mqqvVendor Advisory
- https://access.redhat.com/errata/RHSA-2026:34608
- https://access.redhat.com/errata/RHSA-2026:37272
- https://access.redhat.com/errata/RHSA-2026:40974
- https://access.redhat.com/errata/RHSA-2026:54435
- https://access.redhat.com/security/cve/CVE-2026-44574
- https://bugzilla.redhat.com/show_bug.cgi?id=2477207
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44574.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.