Описание
Servify-express rate limit issue
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
Ссылки
- https://github.com/Aarondoran/servify-express/security/advisories/GHSA-qgc4-8p88-4w7m
- https://nvd.nist.gov/vuln/detail/CVE-2025-67731
- https://github.com/Aarondoran/servify-express/commit/197d848e5450bf85b0dd19ef8c2aa4ba96192300
- https://github.com/Aarondoran/servify-express/commit/8dff7f56504b356278d849734ef2050e5cd23b61
- https://github.com/Aarondoran/servify-express/releases/tag/V1.2
Пакеты
servify-express
<= 1.1
1.2
Связанные уязвимости
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.