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.

The version of Next.js installed on the remote host is 12.0.0 prior to 15.5.21 or 16.0.0 prior to 16.2.11. It is, therefore, affected by multiple vulnerabilities:

- A Server-Side Request Forgery vulnerability in rewrites via an attacker-controlled destination hostname. (CVE-2026-64645)

- A Server-Side Request Forgery vulnerability in Server Actions on custom servers. This issue only affects versions 14.1.1 and later. (CVE-2026-64649)

- A Middleware / Proxy bypass in App Router applications using Turbopack and a single locale. This issue only affects versions 16.0.0 and later. (CVE-2026-64642)

- A denial of service vulnerability in App Router applications using Server Actions. This issue only affects versions 13.0.0 and later. (CVE-2026-64641)

- A denial of service vulnerability due to unbounded Server Action payloads in the Edge runtime. This issue only affects versions 13.0.0 and later. (CVE-2026-64646)

- A denial of service vulnerability in the Image Optimization API using SVGs. This issue only affects versions 15.5.0 and later. (CVE-2026-64644)

- A cache confusion of response bodies for requests with bodies. This issue only affects versions 13.0.0 and later. (CVE-2026-64648)

- A cache confusion of response bodies for requests with bodies containing invalid UTF-8 byte sequences. This issue only affects versions 13.0.0 and later. (CVE-2026-64647)

- An unauthenticated disclosure of internal Server Function endpoints. This issue only affects versions 13.0.0 and later. (CVE-2026-64643)

Note that the scanner has not attempted to exploit these issues but has instead relied only on application's self-reported version number.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - 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. (CVE-2026-64649)

The Next.js Framework on the remote host is affected by a server-side request forgery vulnerability:

  - 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 is also possible to obtain internal values     that weaken middleware/proxy authorization. (CVE-2026-64649)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
115757	Next.js 16.0.x < 16.2.11 Multiple Vulnerabilities	Web App Scanning	Component Vulnerability	Version Based	high
115756	Next.js 12.0.0 < 15.5.21 Multiple Vulnerabilities	Web App Scanning	Component Vulnerability	Version Based	high
455322	Echo: next: security update to 15.5.21	Tenable Cloud Security	Echo Local Security Checks	Local	high
455322	Echo: next: security update to 15.5.21	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	high
330088	Next.js Framework 14.1.1 < 15.5.21 / 16.x < 16.2.11 SSRF	Nessus	Misc.	Local	high
445132	SCA: security update for next (GHSA-89xv-2m56-2m9x)	Tenable Cloud Security	SCA Checks	Local	high
445132	SCA: security update for next (GHSA-89xv-2m56-2m9x)	Tenable Self-Hosted Container Security	SCA Checks	Local	high

Detections

Analytics

CVE-2026-64649

high

Tenable Plugins

high

high

high

high

high

high

high