Headline
GHSA-w37m-7fhw-fmv9: Next Server Actions Source Code Exposure
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.
- GitHub Advisory Database
- GitHub Reviewed
- GHSA-w37m-7fhw-fmv9
Next Server Actions Source Code Exposure
Moderate severity GitHub Reviewed Published Dec 11, 2025 in vercel/next.js
Affected versions
>= 15.0.0-canary.0, < 15.0.6
>= 15.1.1-canary.0, < 15.1.10
>= 15.2.0-canary.0, < 15.2.7
>= 15.3.0-canary.0, < 15.3.7
>= 15.4.0-canary.0, < 15.4.9
>= 15.5.1-canary.0, < 15.5.8
>= 15.6.0-canary.0, < 15.6.0-canary.59
>= 16.0.0-beta.0, < 16.0.9
>= 16.1.0-canary.0, < 16.1.0-canary.17
Patched versions
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
Published to the GitHub Advisory Database
Dec 11, 2025