CVE-2026-64649
Next.js: Server-Side Request Forgery in Server Actions on Custom Servers
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Analyzed | 4.0 | High8.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.46% · top 60% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.3.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
References (5)
- https://github.com/vercel/next.js/security/advisories/GHSA-89xv-2m56-2m9x (opens in a new tab)x_refsource_CONFIRM
- https://github.com/vercel/next.js/commit/b51206321854193208c0805ba42acc49287f942b (opens in a new tab)x_refsource_MISC
- https://github.com/vercel/next.js/commit/e3e5666ccead3a15162793d697af5e48b7cc0498 (opens in a new tab)x_refsource_MISC
- https://github.com/vercel/next.js/releases/tag/v15.5.21 (opens in a new tab)x_refsource_MISC
- https://github.com/vercel/next.js/releases/tag/v16.2.11 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-89xv-2m56-2m9x (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-64649)Record last updated .