# CVE-2026-64649: Next.js: Server-Side Request Forgery in Server Actions on Custom Servers

> CVE-2026-64649: Next.js: Server-Side Request Forgery in Server Actions on Custom Servers. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-64649
Last updated: 2026-10-24T13:10:00Z

- Published: 2026-07-27 19:27 UTC · Updated: 2026-10-24 13:10 UTC · Assigner: GitHub\_M
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- EPSS: 0.46%, 40th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-918

## Description

Next.js is a React framework for building full-stack web applications. In versions 14.1.1 through 15.5.20 and 16.0.0 through 16.2.10, when a Server Action forwards or redirects a request, an attacker can cause the server to send that outbound request to a malicious host (Server-Side Request Forgery). This requires the attacker's request to control Host-associated headers. In some configurations, it's also possible to obtain internal values that weaken middleware/proxy authorization. Applications that use Server Actions are affected when the incoming host header is not fixed to a trusted value. This typically occurs on custom servers, or on deployments not behind a proxy that pins the host. Managed hosting pins the host upstream and is not affected; next start and standalone output do the same from version 14.2 onward. This issue has been fixed in versions 15.5.21 and 16.2.11.

## 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-2026-64649)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-64649)
- [https://github.com/vercel/next.js/commit/b51206321854193208c0805ba42acc49287f942b](https://github.com/vercel/next.js/commit/b51206321854193208c0805ba42acc49287f942b)
- [https://github.com/vercel/next.js/commit/e3e5666ccead3a15162793d697af5e48b7cc0498](https://github.com/vercel/next.js/commit/e3e5666ccead3a15162793d697af5e48b7cc0498)
- [https://github.com/vercel/next.js/releases/tag/v15.5.21](https://github.com/vercel/next.js/releases/tag/v15.5.21)
- [https://github.com/vercel/next.js/releases/tag/v16.2.11](https://github.com/vercel/next.js/releases/tag/v16.2.11)
- [https://github.com/vercel/next.js/security/advisories/GHSA-89xv-2m56-2m9x](https://github.com/vercel/next.js/security/advisories/GHSA-89xv-2m56-2m9x)

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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-2026-64649 · Markdown: https://rewindex.com/cve/CVE-2026-64649.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-64649 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:10:19.216Z