CVE-2021-21322 : Vulnerability Insights and Analysis

fastify-http-proxy is an npm package that acts as a fastify plugin for proxying HTTP requests to another server. A vulnerability in versions prior to 4.3.1 allows an attacker to escape the prefix of the proxied backend service, potentially leading to unauthorized access. Read on to understand the impact, technical details, and mitigation steps related to CVE-2021-21322.

Understanding CVE-2021-21322

This section provides insights into the vulnerability discovered in fastify-http-proxy versions before 4.3.1.

What is CVE-2021-21322?

CVE-2021-21322 involves improper input validation in fastify-http-proxy, allowing an attacker to bypass the prefix of the proxied backend service in affected versions.

The Impact of CVE-2021-21322

The impact of this vulnerability is classified as critical, with a CVSS base score of 10. It poses a high risk to confidentiality and integrity as an attacker can access unauthorized resources.

Technical Details of CVE-2021-21322

In this section, we delve into the specifics of CVE-2021-21322.

Vulnerability Description

The vulnerability arises due to improper input validation, enabling an attacker to escape the prefix of the proxied backend service.

Affected Systems and Versions

fastify-http-proxy versions prior to 4.3.1 are affected by this security flaw.

Exploitation Mechanism

By crafting a specific URL, the attacker can bypass the prefix of the proxied backend service and gain unauthorized access.

Mitigation and Prevention

Here are essential steps to mitigate and prevent exploitation of CVE-2021-21322.

Immediate Steps to Take

Users are advised to update fastify-http-proxy to version 4.3.1 or later to prevent the vulnerability from being exploited.

Long-Term Security Practices

Regularly update and patch all software components to prevent known vulnerabilities from being exploited.

Patching and Updates

Keep track of security advisories and update fastify-http-proxy promptly to stay protected against potential threats.