CVE-2025-59471
Published: 26 January 2026
Summary
CVE-2025-59471 is a medium-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Vercel Next.Js. Its CVSS base score is 5.9 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 12.9th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SI-10 (Information Input Validation).
Deeper analysis
CVE-2025-59471 is a denial-of-service vulnerability in self-hosted Next.js applications that have configured `remotePatterns` for the Image Optimizer. The image optimization endpoint (`/_next/image`) loads external images entirely into memory without enforcing a maximum size limit. This affects Next.js versions prior to 15.5.10 and 16.1.5, with a CVSS v3.1 base score of 5.9 (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H) and is associated with CWE-400 (Uncontrolled Resource Consumption).
An attacker can exploit this vulnerability over the network by requesting optimization of arbitrarily large images hosted on domains permitted by the application's `remotePatterns` configuration. The attacker must be able to serve or control a large image on an allowed external domain, which triggers excessive memory consumption and potential out-of-memory conditions, leading to denial of service. No privileges or user interaction are required, though high attack complexity is needed due to the configuration prerequisites.
The official advisory from Vercel recommends upgrading to Next.js 15.5.10 or 16.1.5 to mitigate the issue and prevent availability disruptions. Details are available in the GitHub Security Advisory at https://github.com/vercel/next.js/security/advisories/GHSA-9g9p-9gw9-jx7f.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-206334
Vulnerability details
A denial of service 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…
more
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 or 16.1.5 to reduce risk and prevent availability issues in Next applications.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Vulnerability directly enables application exploitation causing resource exhaustion and DoS on the image optimization endpoint.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires mechanisms to protect against resource-exhaustion DoS attacks on the /_next/image endpoint.
Mandates validation of externally supplied image data to enforce size limits before full in-memory loading.
Requires controls that limit per-request resource allocation to preserve availability under large-image requests.