CVE-2026-45109

HIGH7.5EPSS 0.01%

Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes - Incomplete Fix Follow-Up

Published: 5/11/2026Modified: 5/14/2026

Also known as:GHSA-26hh-7cqf-hhc6CGA-vxvh-xxgr-xxcc

Description

### Impact It was found that the fix addressing [CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f) did not apply to `middleware.ts` with Turbopack. Refer to [CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f) for further details. ### References - [CVE CVE-2026-44575](https://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f)

Affected packages (1)

npm/next>= 15.2.0, < 15.5.18

CVSS scores

Source	Version	Severity	Vector
osv	CVSS 3.1	HIGH7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References (6)

ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-45109
PATCHhttps://github.com/vercel/next.js
WEBhttps://github.com/vercel/next.js/releases/tag/v15.5.18
WEBhttps://github.com/vercel/next.js/releases/tag/v16.2.6
WEBhttps://github.com/vercel/next.js/security/advisories/GHSA-267c-6grr-h53f
WEBhttps://github.com/vercel/next.js/security/advisories/GHSA-26hh-7cqf-hhc6