CVE-2025-55184 — react-server-dom-parcel
HIGHCVE-2025-55184 is a high-severity (CVSS 7.5) Deserialization of Untrusted Data vulnerability in react-server-dom-parcel. 3 public exploit references exist, so weaponization risk is real. A fix is available for react-server-dom-parcel — see the affected versions and patch details below.
Denial of Service Vulnerability in React Server Components
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-55184.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-55184 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
react-server-dom-parcelnpmreact-server-dom-turbopacknpmreact-server-dom-webpacknpmDescription
A pre-authentication denial of service vulnerability exists in 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. The vulnerable code unsafely deserializes payloads from HTTP requests to Server Function endpoints, which can cause an infinite loop that hangs the server process and may prevent future HTTP requests from being served.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | react-server-dom-parcel | ≥ 19.0.0&&< 19.0.2 | 19.0.2npm install react-server-dom-parcel@19.0.2 |
| 📦npm | react-server-dom-turbopack | ≥ 19.0.0&&< 19.0.2 | 19.0.2npm install react-server-dom-turbopack@19.0.2 |
| 📦npm | react-server-dom-webpack | ≥ 19.0.0&&< 19.0.2 | 19.0.2npm install react-server-dom-webpack@19.0.2 |
| 📦npm | react-server-dom-parcel | ≥ 19.1.0&&< 19.1.3 | 19.1.3npm install react-server-dom-parcel@19.1.3 |
| 📦npm | react-server-dom-parcel | ≥ 19.2.0&&< 19.2.2 | 19.2.2npm install react-server-dom-parcel@19.2.2 |
| 📦npm | react-server-dom-turbopack | ≥ 19.1.0&&< 19.1.3 | 19.1.3npm install react-server-dom-turbopack@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.
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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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-2025-55184 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-55184 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-55184. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect CVE-2025-55184
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2025-55184 -u https://target- Template
- React Server Components - Denial of Service
- Severity
- high
- Impact
- Unauthenticated attackers can cause the server to hang indefinitely, resulting in denial of service and preventing legitimate requests.
- Remediation
- Update to the latest version beyond 19.2.1.
Template by ProjectDiscovery nuclei-templates (DhiyaneshDk), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2025-55184 in your dependencies?
O3 Security finds CVE-2025-55184 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.