CVE-2021-23385 : What You Need to Know

A detailed guide on CVE-2021-23385, a vulnerability affecting all versions of Flask-Security that allows bypassing URL validation and redirecting users to arbitrary URLs. This vulnerability is exploitable under specific conditions related to alternative WSGI servers.

Understanding CVE-2021-23385

This section delves into the specifics of CVE-2021-23385, its impact, technical details, and mitigation strategies.

What is CVE-2021-23385?

CVE-2021-23385 is an open redirect vulnerability found in all versions of Flask-Security. If certain conditions are met, attackers can bypass URL validation and redirect users to malicious websites.

The Impact of CVE-2021-23385

This vulnerability poses a moderate risk, allowing threat actors to manipulate user redirection and potentially lead them to malicious websites, posing a security threat to user data and privacy.

Technical Details of CVE-2021-23385

This section examines the vulnerability description, affected systems, and the exploitation mechanism.

Vulnerability Description

Flask-Security is affected by a flaw that enables attackers to exploit URL validation bypass when using specific functions and configurations.

Affected Systems and Versions

All versions of Flask-Security are impacted by CVE-2021-23385. Users are advised to take immediate action to mitigate the risk.

Exploitation Mechanism

By providing multiple backslashes in URLs, attackers can trick the system into redirecting users to arbitrary locations, potentially leading to further exploitation.

Mitigation and Prevention

Learn how to safeguard your systems against CVE-2021-23385 and prevent potential security breaches.

Immediate Steps to Take

Security professionals recommend reviewing and updating server configurations related to URL validation and redirection, limiting potential attack vectors.

Long-Term Security Practices

Implement strict URL validation and perform regular security audits to detect and address vulnerabilities in Flask-Security and related components.

Patching and Updates

Stay informed about security patches and updates released by Flask-Security to address the CVE-2021-23385 vulnerability.