CVE-2025-49005

LOW3.7EPSS 0.43%

Next.js has a Cache poisoning vulnerability due to omission of the Vary header

Published: 7/3/2025Modified: 2/4/2026

Description

### Summary A cache poisoning issue in **Next.js App Router >=15.3.0 and < 15.3.3** may have allowed RSC payloads to be cached and served in place of HTML, under specific conditions involving middleware and redirects. This issue has been fixed in **Next.js 15.3.3**. Users on affected versions should **upgrade immediately** and **redeploy** to ensure proper caching behavior. More details: [CVE-2025-49005](https://vercel.com/changelog/cve-2025-49005)

Affected packages (1)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1LOW3.7CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

References (8)