CVE-2021-22964 : Exploit Details and Defense Strategies

A redirect vulnerability in the

fastify-static

module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash

//

followed by a domain. A denial of service (DOS) vulnerability can occur if the URL contains invalid characters. The issue affects applications that set the

redirect: true

option.

Understanding CVE-2021-22964

This CVE involves a redirect vulnerability in the

fastify-static

module that can lead to Mozilla Firefox users being redirected to malicious websites.

What is CVE-2021-22964?

The CVE-2021-22964 refers to a redirect vulnerability in the

fastify-static

module that allows remote attackers to redirect users to arbitrary websites by manipulating the URL.

The Impact of CVE-2021-22964

The impact of this CVE is significant as it enables attackers to redirect users to malicious sites, potentially leading to further exploitation or unauthorized access.

Technical Details of CVE-2021-22964

This section covers specific technical details related to CVE-2021-22964.

Vulnerability Description

The vulnerability in the

fastify-static

module versions >= 4.2.4 and < 4.4.1 allows for URL manipulation, leading to unauthorized redirection of users.

Affected Systems and Versions

Systems using the

fastify-static

module with versions >= 4.2.4 and < 4.4.1 are vulnerable to this exploit.

Exploitation Mechanism

Attackers can exploit this vulnerability by inserting a double slash

//

in the URL followed by a domain to redirect users to arbitrary websites.

Mitigation and Prevention

To address CVE-2021-22964, certain mitigation and prevention measures can be implemented.

Immediate Steps to Take

Update the

fastify-static

module to version 4.4.1 or higher to prevent exploitation of this vulnerability.
Avoid using the

redirect: true

option in

fastify-static

applications.

Long-Term Security Practices

Regularly monitor for security updates and patches for the

fastify-static

module.
Conduct security audits to identify and address any similar vulnerabilities in the application.

Patching and Updates

Ensure that all systems using the

fastify-static

module are updated to version 4.4.1 or above to mitigate the risks associated with CVE-2021-22964.