Uncontrolled Resource Consumption
This affects the package npm-user-validate before 1.0.1. The regex that validates user emails took exponentially longer to process long input strings beginning with @ characters.
CWE-400 - Uncontrolled resource consumption
An uncontrolled resource allocation attack (also known as resource exhaustion attack) triggers unauthorized overconsumption of the limited resources in an application, such as memory, file system storage, database connection pool entries, and CPU. This may lead to denial of service for valid users and degradation of the application's functionality as well as that of the host operating system.