Summary
Next.js: Denial of Service in the Image Optimization API using SVGs
Workarounds
If you cannot upgrade immediately, you can avoid the expensive work by setting config.experimental.imgOptSkipMetadata : true.
Impact
When self-hosting Next.js with the default image loader, the Image Optimization API can optimize remotely hosted images if configured (not enabled by default). If those images contain malicious content, they can cause CPU exhaustion in /_next/image endpoints.
- If you are using
config.images.remotePatterns, only the patterns in that array are impacted. - If you are using
config.images.unoptimized: true, you are NOT impacted. - If you are using
config.images.loader: 'custom', you are NOT impacted. - If you are using Vercel, you are NOT impacted.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
next to 15.5.21 or later; next to 16.2.11 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2026-64644? CVE-2026-64644 is a medium-severity security vulnerability in next (npm), affecting versions >= 15.5.0, < 15.5.21. It is fixed in 15.5.21, 16.2.11.
- Which versions of next are affected by CVE-2026-64644? next (npm) versions >= 15.5.0, < 15.5.21 is affected.
- Is there a fix for CVE-2026-64644? Yes. CVE-2026-64644 is fixed in 15.5.21, 16.2.11. Upgrade to this version or later.
- Is CVE-2026-64644 exploitable, and should I be worried? Whether CVE-2026-64644 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
- What actually determines whether CVE-2026-64644 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.
- How do I fix CVE-2026-64644?
- Upgrade
nextto 15.5.21 or later - Upgrade
nextto 16.2.11 or later
- Upgrade