CVE-2020-7754 : Exploit Details and Defense Strategies

This CVE-2020-7754 article provides insights into a Regular Expression Denial of Service (ReDoS) vulnerability affecting npm-user-validate before version 1.0.1.

Understanding CVE-2020-7754

This vulnerability, assigned CVE-2020-7754, impacts the npm-user-validate package, potentially leading to denial of service due to inefficient processing of long input strings.

What is CVE-2020-7754?

CVE-2020-7754 is a Regular Expression Denial of Service (ReDoS) vulnerability in npm-user-validate versions prior to 1.0.1. It arises from the extended processing time of email validation regex for strings starting with @ characters.

The Impact of CVE-2020-7754

The vulnerability has a CVSS v3.1 base score of 7.5, indicating a high severity issue with a significant impact on availability.

Technical Details of CVE-2020-7754

Vulnerability Description

The regex used for email validation in npm-user-validate before 1.0.1 causes a significant delay in processing long input strings starting with @ characters, potentially leading to a denial of service.

Affected Systems and Versions

Product: npm-user-validate
Vendor: n/a
Versions Affected: < 1.0.1

Exploitation Mechanism

The vulnerability can be exploited by sending specially crafted input strings to the email validation function, triggering the inefficient regex processing and causing a denial of service.

Mitigation and Prevention

Immediate Steps to Take

Update npm-user-validate to version 1.0.1 or higher to mitigate the vulnerability.
Avoid processing untrusted input that may trigger the ReDoS vulnerability.

Long-Term Security Practices

Regularly monitor for security advisories and updates related to npm-user-validate.
Implement input validation mechanisms to prevent malicious inputs.

Patching and Updates

Apply patches and updates provided by the npm-user-validate package maintainers to address the ReDoS vulnerability.