GHSA-W37M-7FHW-FMV9

A vulnerability affects certain React packages for versions 19.0.0, 19.0.1, 19.1.0, 19.1.1, 19.1.2, 19.2.0, and 19.2.1 and frameworks that use the affected packages, including Next.js 15.x and 16.x using the App Router. The issue is tracked upstream as CVE-2025-55183.

A malicious HTTP request can be crafted and sent to any App Router endpoint that can return the compiled source code of Server Functions. This could reveal business logic, but would not expose secrets unless they were hardcoded directly into Server Function code.

Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect. Typical impact: arbitrary code execution or logic abuse.

GHSA-W37M-7FHW-FMV9 has a CVSS score of 5.3 (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 (15.0.6, 15.1.10, 15.2.7, 15.3.7, 15.4.9, 15.5.8, 15.6.0-canary.59, 16.0.9, 16.1.0-canary.17); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is GHSA-W37M-7FHW-FMV9? GHSA-W37M-7FHW-FMV9 is a medium-severity insecure deserialization vulnerability in next (npm), affecting versions >= 15.0.0-canary.0, < 15.0.6. It is fixed in 15.0.6, 15.1.10, 15.2.7, 15.3.7, 15.4.9, 15.5.8, 15.6.0-canary.59, 16.0.9, 16.1.0-canary.17. Untrusted serialized data is processed by a deserializer that can instantiate arbitrary objects or execute code as a side effect.
2. How severe is GHSA-W37M-7FHW-FMV9? GHSA-W37M-7FHW-FMV9 has a CVSS score of 5.3 (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 GHSA-W37M-7FHW-FMV9? next (npm) versions >= 15.0.0-canary.0, < 15.0.6 is affected.
4. Is there a fix for GHSA-W37M-7FHW-FMV9? Yes. GHSA-W37M-7FHW-FMV9 is fixed in 15.0.6, 15.1.10, 15.2.7, 15.3.7, 15.4.9, 15.5.8, 15.6.0-canary.59, 16.0.9, 16.1.0-canary.17. Upgrade to this version or later.
5. Is GHSA-W37M-7FHW-FMV9 exploitable, and should I be worried? Whether GHSA-W37M-7FHW-FMV9 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 GHSA-W37M-7FHW-FMV9 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 GHSA-W37M-7FHW-FMV9?
   • Upgrade next to 15.0.6 or later
   • Upgrade next to 15.1.10 or later
   • Upgrade next to 15.2.7 or later
   • Upgrade next to 15.3.7 or later
   • Upgrade next to 15.4.9 or later
   • Upgrade next to 15.5.8 or later
   • Upgrade next to 15.6.0-canary.59 or later
   • Upgrade next to 16.0.9 or later
   • Upgrade next to 16.1.0-canary.17 or later