CVE-2025-59471

A DoS vulnerability exists in self-hosted Next.js applications that have remotePatterns configured for the Image Optimizer. The image optimization endpoint (/_next/image) loads external images entirely into memory without enforcing a maximum size limit, allowing an attacker to cause out-of-memory conditions by requesting optimization of arbitrarily large images. This vulnerability requires that remotePatterns is configured to allow image optimization from external domains and that the attacker can serve or control a large image on an allowed domain.

Strongly consider upgrading to 15.5.10 and 16.1.5 to reduce risk and prevent availability issues in Next applications.

Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.

CVE-2025-59471 has a CVSS score of 5.9 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (15.5.10, 16.1.5); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2025-59471? CVE-2025-59471 is a medium-severity uncontrolled resource consumption vulnerability in next (npm), affecting versions >= 10.0.0, < 15.5.10. It is fixed in 15.5.10, 16.1.5. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
2. How severe is CVE-2025-59471? CVE-2025-59471 has a CVSS score of 5.9 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of next are affected by CVE-2025-59471? next (npm) versions >= 10.0.0, < 15.5.10 is affected.
4. Is there a fix for CVE-2025-59471? Yes. CVE-2025-59471 is fixed in 15.5.10, 16.1.5. Upgrade to this version or later.
5. Is CVE-2025-59471 exploitable, and should I be worried? Whether CVE-2025-59471 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2025-59471 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2025-59471?
   • Upgrade next to 15.5.10 or later
   • Upgrade next to 16.1.5 or later