Vulnerability in Vercel Next.js
CVE-2026-45109
Next.js is a React framework for building full-stack web applications. From 15.2.0 to before 15.5.18 and 16.2.6, it was found that the fix addressing CVE-2026-44575 did not apply to middleware.ts with Turbopack. This vulnerability is fixed in 15.5.18 and 16.2.6.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.008 (53.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 53.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.008 · change: +0.002
Affected products
- Vercel Next.js — versions >= 15.2.0, < 15.5.17, >= 16.0.0, < 16.2.6
Weakness classification (CWE)
References
- github.com/vercel/next.js/security/advisories/GHSA-26hh-7cqf-hhc6 (Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-45109?
- CVE-2026-45109 is a high-severity vulnerability in Vercel Next.js, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 7.5/10. Published 2026-05-13.
- How severe is CVE-2026-45109?
- High severity. CVSS v3 base score is 7.5 out of 10.