GHSA-w37m-7fhw-fmv9
MEDIUMNext Server Actions Source Code Exposure
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
nextnpmDescription
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | next | ≥ 15.0.0-canary.0&&< 15.0.6 | 15.0.6 |
| 📦npm | next | ≥ 15.1.1-canary.0&&< 15.1.10 | 15.1.10 |
| 📦npm | next | ≥ 15.2.0-canary.0&&< 15.2.7 | 15.2.7 |
| 📦npm | next | ≥ 15.3.0-canary.0&&< 15.3.7 | 15.3.7 |
| 📦npm | next | ≥ 15.4.0-canary.0&&< 15.4.9 | 15.4.9 |
| 📦npm | next | ≥ 15.5.1-canary.0&&< 15.5.8 | 15.5.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for next. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update next to 15.0.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w37m-7fhw-fmv9 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-w37m-7fhw-fmv9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-w37m-7fhw-fmv9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-w37m-7fhw-fmv9 in your dependencies?
O3 detects GHSA-w37m-7fhw-fmv9 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.