CVE-2025-55183
MEDIUMCVE-2025-55183 is a medium-severity (CVSS 5.3) vulnerability in react-server-dom-parcel. 4 public exploit references exist, so weaponization risk is real. O3 Security confirms whether CVE-2025-55183 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Source Code Exposure Vulnerability in React Server Components
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
react-server-dom-parcelnpmreact-server-dom-turbopacknpmreact-server-dom-webpacknpmDescription
An information leak vulnerability exists in specific configurations of React Server Components versions 19.0.0, 19.0.1 19.1.0, 19.1.1, 19.1.2, 19.2.0 and 19.2.1, including the following packages: react-server-dom-parcel, react-server-dom-turbopack, and react-server-dom-webpack. A specifically crafted HTTP request sent to a vulnerable Server Function may unsafely return the source code of any Server Function. Exploitation requires the existence of a Server Function which explicitly or implicitly exposes a stringified argument.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | react-server-dom-parcel | ≥ 19.0.0&&< 19.0.2 | 19.0.2 |
| 📦npm | react-server-dom-turbopack | ≥ 19.0.0&&< 19.0.2 | 19.0.2 |
| 📦npm | react-server-dom-webpack | ≥ 19.0.0&&< 19.0.2 | 19.0.2 |
| 📦npm | react-server-dom-parcel | ≥ 19.1.0&&< 19.1.3 | 19.1.3 |
| 📦npm | react-server-dom-parcel | ≥ 19.2.0&&< 19.2.2 | 19.2.2 |
| 📦npm | react-server-dom-turbopack | ≥ 19.1.0&&< 19.1.3 | 19.1.3 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
williavs/nextjs-security-update
Batch upgrade all your Next.js apps to patched versions - fight back aga
kimtruth/CVE-2025-55183-poc
PoC for CVE-2025-55183
StealthMoud/react-server-cve-lab
Security research lab for CVE-2025-55183 and CVE-2025-55184 in React Ser
X-Cotang/CVE-2025-55183_POC
CVE-2025-55183 POC
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for react-server-dom-parcel. 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 react-server-dom-parcel to 19.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-55183 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 CVE-2025-55183 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 CVE-2025-55183. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-55183 in your dependencies?
O3 detects CVE-2025-55183 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.