CVE-2021-36172 : Vulnerability Insights and Analysis

This article provides detailed information about CVE-2021-36172, an improper restriction of XML external entity reference vulnerability in Fortinet FortiPortal before 6.0.6 that could lead to denial of service attacks and arbitrary file reading.

Understanding CVE-2021-36172

CVE-2021-36172 is a vulnerability in Fortinet FortiPortal before version 6.0.6 that arises from an improper restriction of XML external entity reference in the parser of XML responses.

What is CVE-2021-36172?

The vulnerability allows an attacker who controls the producer of XML reports consumed by FortiPortal to trigger denial of service or read arbitrary files from the underlying file system using specially crafted XML documents.

The Impact of CVE-2021-36172

The impact of this vulnerability is rated as low severity. However, it could potentially lead to information disclosure from the affected system.

Technical Details of CVE-2021-36172

The technical details of CVE-2021-36172 based on CVSS v3.1 are as follows:

Vulnerability Description

Attack Complexity: Low
Attack Vector: Network
Confidentiality Impact: Low
Integrity Impact: None
Privileges Required: Low

Affected Systems and Versions

The vulnerability affects Fortinet FortiPortal versions before 6.0.6.

Exploitation Mechanism

The vulnerability can be exploited by an attacker who controls the producer of XML reports consumed by FortiPortal through specially crafted XML documents.

Mitigation and Prevention

To mitigate the risks associated with CVE-2021-36172, consider the following:

Immediate Steps to Take

Apply the workaround provided by Fortinet until a comprehensive fix is available.

Long-Term Security Practices

Regularly update FortiPortal software to the latest version to ensure protection against known vulnerabilities.

Patching and Updates

Keep abreast of security advisories from Fortinet and promptly apply patches and updates to FortiPortal.