Node.js URL.format() Crash via Malformed IDN
CVE-2026-21712 Published on March 30, 2026
A flaw in Node.js URL processing causes an assertion failure in native code when `url.format()` is called with a malformed internationalized domain name (IDN) containing invalid characters, crashing the Node.js process.
Weakness Type
Improper Input Validation
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
Affected Versions
nodejs node:- Version 24.14.0, <= 24.14.0 is affected.
- Version 25.8.1, <= 25.8.1 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.