CVE-2025-67731 — servify-express
Fix: Aarondoran/servify-express@8dff7f5CVE-2025-67731 is a Uncontrolled Resource Consumption vulnerability in servify-express. A fix is available for servify-express — see the affected versions and patch details below.
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.
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.
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.
servify-expressnpmDescription
Impact
The Express server uses express.json() without a size limit, which can allow attackers to send extremely large request bodies. This may lead to 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.
Patches
This issue is not a flaw in Express itself but in configuration. Users should set a request-size limit when enabling the JSON body parser. For example:
app.use(express.json({ limit: "100kb" }));
Workarounds
Users can mitigate the issue without upgrading by:
- Adding a
limitoption to the JSON parser - Implementing rate limiting at the application or reverse-proxy level
- Rejecting unusually large requests before parsing
- 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 | 1.2npm install servify-express@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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-67731 can be triaged on real exposure rather than presence alone.
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 Security finds CVE-2025-67731 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.