CVE-2025-67731
Fix: Aarondoran/servify-express@8dff7f5CVE-2025-67731 is a Uncontrolled Resource Consumption vulnerability in servify-express. O3 Security confirms whether CVE-2025-67731 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Servify Express does not enforce rate limiting when parsing JSON
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-67731.
Real-World Exposure
servify-expressReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Servify Express is a Node.js package to start an Express server and log the port it's running on. Prior to 1.2, the Express server used express.json() without a size limit, which could allow attackers to send extremely large request bodies. This can cause excessive memory usage, degraded performance, or process crashes, resulting in a Denial of Service (DoS). Any application using the JSON parser without limits and exposed to untrusted clients is affected. The issue is not a flaw in Express itself, but in configuration. This issue is fixed in version 1.2. To work around, consider adding a limit option to the JSON parser, rate limiting at the application or reverse-proxy level, rejecting unusually large requests before parsing, or using a reverse proxy (such as NGINX) to enforce maximum request body sizes.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | servify-express | all versions | 1.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for servify-express. 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 servify-express to 1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-67731 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-2025-67731 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-2025-67731. 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-2025-67731 in your dependencies?
O3 detects CVE-2025-67731 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.