CVE-2025-49005: Next.js cache poisoning due to omission of Vary header
Description
Next.js is a React framework for building full-stack web applications. In Next.js App Router from 15.3.0 to before 15.3.3 and Vercel CLI from 41.4.1 to 42.2.0, a cache poisoning vulnerability was found. The issue allowed page requests for HTML content to return a React Server Component (RSC) payload instead under certain conditions. When deployed to Vercel, this would only impact the browser cache, and would not lead to the CDN being poisoned. When self-hosted and deployed externally, this could lead to cache poisoning if the CDN does not properly distinguish between RSC / HTML in the cache keys. This issue has been resolved in Next.js 15.3.3.
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N · CWE-444
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
vercel: next.js
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/vercel/next.js/commit/ec202eccf05820b60c6126d6411fe16766ecc066 (opens in new tab)
- github.com/vercel/next.js/issues/79346 (opens in new tab)
- github.com/vercel/next.js/releases/tag/v15.3.3 (opens in new tab)
- github.com/vercel/next.js/security/advisories/GHSA-r2fc-ccr8-96c4 (opens in new tab)
- vercel.com/changelog/cve-2025-49005 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)