Summary
Security Advisory: express-xss-sanitizer
Overview
A vulnerability was discovered in express-xss-sanitizer that allowed unbounded recursion depth during sanitization of nested objects.
Affected Versions
- All versions prior to 2.0.1
Patched Versions
- 2.0.1 and later
Description
The sanitize function in lib/sanitize.js performed recursive sanitization without depth limiting, making it vulnerable to stack overflow attacks via specially crafted deeply nested JSON objects.
Impact
An attacker could cause denial-of-service by sending a request with deeply nested structures, potentially crashing the Node.js process.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Upgrade to version 2.0.1 or later:
npm install express-xss-sanitizer@latest
Frequently Asked Questions
- What is CVE-2025-59364? CVE-2025-59364 is a medium-severity security vulnerability in express-xss-sanitizer (npm), affecting versions < 2.0.1. It is fixed in 2.0.1.
- Which versions of express-xss-sanitizer are affected by CVE-2025-59364? express-xss-sanitizer (npm) versions < 2.0.1 is affected.
- Is there a fix for CVE-2025-59364? Yes. CVE-2025-59364 is fixed in 2.0.1. Upgrade to this version or later.
- Is CVE-2025-59364 exploitable, and should I be worried? Whether CVE-2025-59364 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-59364 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-59364? Upgrade
express-xss-sanitizerto 2.0.1 or later.