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.

Scores

Weaknesses (CWE)

• CWE-444

Advisories

• GHSA-r2fc-ccr8-96c4 — Next.js has a Cache poisoning vulnerability due to omission of the Vary header

European references

• ENISA EUVD · EUVD-2025-19911
• GCVE · GCVE-0-2025-49005

CERT-FR advisories

• CERTFR-2025-AVI-0896 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

• cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* ≥ 15.3.0 < 15.3.3
• cpe:2.3:a:vercel:vercel:*:*:*:*:*:*:*:* ≥ 41.4.1 < 42.2.0

Affected products

References

• https://github.com/vercel/next.js/security/advisories/GHSA-r2fc-ccr8-96c4
• https://github.com/vercel/next.js/issues/79346
• https://github.com/vercel/next.js/commit/ec202eccf05820b60c6126d6411fe16766ecc066
• https://github.com/vercel/next.js/releases/tag/v15.3.3
• https://vercel.com/changelog/cve-2025-49005

Sources