CVE-2021-32706 Explained : Impact and Mitigation

Pi-hole's Web interface, specifically versions prior to 5.5.1, is vulnerable to a remote code execution flaw that can allow attackers to execute malicious code, list directories, and overwrite sensitive files. This CVE has a CVSS base score of 7.6, indicating a high severity threat.

Understanding CVE-2021-32706

This CVE, identified as a code injection vulnerability (CWE-94), affects the AdminLTE product by the vendor pi-hole. The issue arises due to a flaw in the

validDomainWildcard

preg_match filter.

What is CVE-2021-32706?

The CVE-2021-32706 vulnerability in Pi-hole's Web interface version < 5.5.1 allows an authenticated attacker to perform remote code execution, potentially compromising the system's integrity.

The Impact of CVE-2021-32706

The impact of this vulnerability is severe, with attackers being able to execute arbitrary code, view sensitive information, and manipulate files on the affected system, posing a significant risk to data confidentiality and system availability.

Technical Details of CVE-2021-32706

The CVSSv3.1 base score for CVE-2021-32706 is 7.6. The attack complexity is low, but the impact on system availability is high. The vulnerability can be exploited over a network without requiring user interaction.

Vulnerability Description

The vulnerability in Pi-hole's Web interface allows attackers to bypass security measures and execute malicious code due to improper input validation.

Affected Systems and Versions

Pi-hole Web interface versions prior to 5.5.1 are affected by this vulnerability.

Exploitation Mechanism

By exploiting the flaw in the

validDomainWildcard

preg_match filter, attackers can insert malicious characters that lead to code execution.

Mitigation and Prevention

To prevent exploitation of this vulnerability, immediate action is required to apply the patch released in version 5.5.1. Additionally, it is crucial to implement long-term security practices and stay updated with software patches.

Immediate Steps to Take

Update the Pi-hole Web interface to version 5.5.1 or later to mitigate the risk of remote code execution.

Long-Term Security Practices

Practice secure coding, input validation, and user privilege management to reduce the likelihood of future vulnerabilities.

Patching and Updates

Regularly monitor for security updates and apply patches promptly to prevent exploitation of known vulnerabilities.