CVE-2025-67731: Servify Express does not enforce rate limiting when parsing JSON

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-12 · updated 2026-10-07
Weakness: CWE-400

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 products

Aarondoran servify-express: before 1.2 — fixed in 1.2

How to fix

Upgrade to a fixed version: Aarondoran servify-express 1.2. Check the vendor advisory for mitigations.

References

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