CVE-2026-45109

CVE-2026-45109 is a high-severity security vulnerability in next (npm), affecting versions >= 15.2.0, < 15.5.18. It is fixed in 15.5.18, 16.2.6.

Summary

References

Impact

It was found that the fix addressing CVE-2026-44575 did not apply to middleware.ts with Turbopack. Refer to CVE-2026-44575 for further details.

CVE-2026-45109 has a CVSS score of 7.5 (High). 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 (15.5.18, 16.2.6); upgrading removes the vulnerable code path.

Affected versions

next (>= 15.2.0, < 15.5.18) next (>= 16.0.0, < 16.2.6)

Security releases

next → 15.5.18 (npm) next → 16.2.6 (npm)

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.

See it in your environment

Remediation advice

Upgrade the following packages to resolve this vulnerability:

next to 15.5.18 or later; next to 16.2.6 or later

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently Asked Questions

  1. What is CVE-2026-45109? CVE-2026-45109 is a high-severity security vulnerability in next (npm), affecting versions >= 15.2.0, < 15.5.18. It is fixed in 15.5.18, 16.2.6.
  2. How severe is CVE-2026-45109? CVE-2026-45109 has a CVSS score of 7.5 (High). 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-2026-45109? next (npm) versions >= 15.2.0, < 15.5.18 is affected.
  4. Is there a fix for CVE-2026-45109? Yes. CVE-2026-45109 is fixed in 15.5.18, 16.2.6. Upgrade to this version or later.
  5. Is CVE-2026-45109 exploitable, and should I be worried? Whether CVE-2026-45109 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-2026-45109 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-2026-45109?
    • Upgrade next to 15.5.18 or later
    • Upgrade next to 16.2.6 or later

Other vulnerabilities in next

CVE-2026-45109CVE-2026-44572CVE-2026-44581CVE-2026-44582CVE-2026-44580

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