CVE-2021-40186 Explained : Impact and Mitigation

DNN CMS platform was identified with an SSRF vulnerability, allowing attackers to make network requests and potentially access sensitive information.

Understanding CVE-2021-40186

This CVE-2021-40186 involves a Server-Side Request Forgery (SSRF) vulnerability within the DNN CMS platform (formerly DotNetNuke).

What is CVE-2021-40186?

SSRF vulnerability identified in DNN CMS platform
Allows attackers to exploit the target system for network requests
Commonly used to attack systems behind firewalls

The Impact of CVE-2021-40186

CVSS Score: 6.5 (Medium Severity)
Attack Complexity: Low
Confidentiality Impact: High
No requirement for user interaction

Technical Details of CVE-2021-40186

This section delves into specific technical aspects of the vulnerability.

Vulnerability Description

Server-Side Request Forgery (SSRF) vulnerability
Allows attackers to make network requests through the target system

Affected Systems and Versions

Product: DNN Platform
Vendor: DNNSoftware
Vulnerable Version: 9.0 (Custom version less than 9.11.0)

Exploitation Mechanism

Attackers exploit SSRF to access systems behind firewalls
Gain unauthorized access to sensitive information stored in cloud metadata services

Mitigation and Prevention

Measures that can be taken to mitigate the risks associated with CVE-2021-40186.

Immediate Steps to Take

Update DNN Platform to version 9.11.0 or above
Implement network level access controls to prevent SSRF attacks

Long-Term Security Practices

Regular security assessments and vulnerability scans
Educate users on SSRF risks and safe browsing practices

Patching and Updates

Stay informed about security patches released by DNNSoftware
Promptly apply software updates to mitigate known vulnerabilities