# CVE-2025-49005: Next.js cache poisoning due to omission of Vary header

> CVE-2025-49005: Next.js cache poisoning due to omission of Vary header. CVSS 3.7 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2025-49005
Last updated: 2026-06-17T09:30:39Z

- Published: 2025-07-03 21:01 UTC · Updated: 2026-06-17 09:30 UTC · Assigner: GitHub\_M
- CVSS: 3.7 (CVSS 3.1) · Severity: Low · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS: 0.49%, 42th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-444

## 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.

## Affected vendors and products

- vercel: next.js

## Tracked companies

- [Vercel](https://rewindex.com/company/vercel.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2025-49005)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2025-49005)
- [https://github.com/vercel/next.js/commit/ec202eccf05820b60c6126d6411fe16766ecc066](https://github.com/vercel/next.js/commit/ec202eccf05820b60c6126d6411fe16766ecc066)
- [https://github.com/vercel/next.js/issues/79346](https://github.com/vercel/next.js/issues/79346)
- [https://github.com/vercel/next.js/releases/tag/v15.3.3](https://github.com/vercel/next.js/releases/tag/v15.3.3)
- [https://github.com/vercel/next.js/security/advisories/GHSA-r2fc-ccr8-96c4](https://github.com/vercel/next.js/security/advisories/GHSA-r2fc-ccr8-96c4)
- [https://vercel.com/changelog/cve-2025-49005](https://vercel.com/changelog/cve-2025-49005)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2025-49005 · Markdown: https://rewindex.com/cve/CVE-2025-49005.md · JSON: https://rewindex.com/api/v1/cves/CVE-2025-49005 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:05:13.666Z