CVE-2014-7191: DoS in qs Node.js Module

An attacker can exploit this vulnerability by sending a malicious string to an application using the qs module. This string, when parsed, triggers the creation of a very large sparse array in memory. The sheer size of this array consumes significant system resources, leading to memory exhaustion. As the application attempts to allocate more memory, it will likely crash, resulting in a denial of service. The blast radius is limited to the affected Node.js application; however, a successful attack could disrupt service availability for users relying on that application. This vulnerability highlights the importance of validating and sanitizing input data to prevent resource exhaustion attacks.

1. Published2017-10-24
2. Modified2023-11-08
3. EPSS updated2026-04-02

The primary mitigation for CVE-2014-7191 is to upgrade the qs module to version 1.0.0 or later. This version includes a fix that prevents the creation of excessively large sparse arrays. If upgrading is not immediately feasible, consider implementing input validation to reject or sanitize strings that are likely to trigger the vulnerability. While not a complete solution, this can reduce the attack surface. Additionally, consider implementing resource limits within the Node.js application to prevent a single process from consuming excessive memory. After upgrading, confirm the fix by attempting to parse a known malicious string and verifying that the application does not crash.