CVE-2021-22131 Explained : Impact and Mitigation

A improper validation of certificate with host mismatch in Fortinet FortiTokenAndroid, Fortinet FortiTokeniOS, Fortinet FortiTokenWinApp allows attackers to retrieve disclosed information. Here's what you should know about CVE-2021-22131.

Understanding CVE-2021-22131

This section provides an overview of the vulnerability and its impact.

What is CVE-2021-22131?

CVE-2021-22131 is a vulnerability in Fortinet's FortiToken products that allows attackers to exploit a host mismatch in certificate validation, leading to information disclosure via man-in-the-middle attacks.

The Impact of CVE-2021-22131

The vulnerability has a CVSS base score of 6.1 (Medium severity) and affects multiple versions of Fortinet's FortiToken products. The attack complexity is high, with confidentiality impact rated as high and no integrity impact. Attackers can exploit this vulnerability without the need for privileges.

Technical Details of CVE-2021-22131

Let's dive into the technical aspects of CVE-2021-22131.

Vulnerability Description

The vulnerability stems from improper validation of certificates with host mismatches in Fortinet FortiTokenAndroid, FortiTokeniOS, and FortiTokenWinApp. Attackers can exploit this to intercept and retrieve sensitive information through man-in-the-middle attacks.

Affected Systems and Versions

Fortinet FortiTokenAndroid versions 5.0.3 and below, FortiTokeniOS versions 5.2.0 and below, FortiTokenWinApp versions 4.0.3 and below are affected by this vulnerability.

Exploitation Mechanism

Attackers can perform man-in-the-middle attacks to exploit the improper certificate validation and retrieve sensitive information from affected FortiToken products.

Mitigation and Prevention

Here are the steps to mitigate the risk posed by CVE-2021-22131.

Immediate Steps to Take

Users should update affected FortiToken products to the latest patched versions to mitigate the vulnerability. Additionally, users should avoid using unsecured networks where man-in-the-middle attacks are more likely.

Long-Term Security Practices

Implementing secure certificate validation practices and monitoring for unusual network activities can help prevent similar attacks in the future.

Patching and Updates

Regularly applying security patches and updates provided by Fortinet is crucial to addressing known vulnerabilities and protecting against evolving threats.