CVE-2021-24033 is a medium-severity (CVSS 5.6) OS Command Injection vulnerability in react-dev-utils. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2021-24033 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
react-dev-utils OS Command Injection in function `getProcessForPort`
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-dev-utilsnpmDescription
react-dev-utils prior to v11.0.4 exposes a function, getProcessForPort, where an input argument is concatenated into a command string to be executed. This function is typically used from react-scripts (in Create React App projects), where the usage is safe. Only when this function is manually invoked with user-provided values (ie: by custom code) is there the potential for command injection. If you're consuming it from react-scripts then this issue does not affect you.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | react-dev-utils | ≥ 0.4.0&&< 11.0.4 | 11.0.4 |
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-dev-utils. 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-dev-utils to 11.0.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-24033 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-2021-24033 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-2021-24033. 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-2021-24033 in your dependencies?
O3 detects CVE-2021-24033 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.