CVE-2021-32556 Explained : Impact and Mitigation

A command injection vulnerability, tracked as CVE-2021-32556, was discovered in the 'apport' package in versions below 2.20.1-0ubuntu2.30+esm1, 2.20.9-0ubuntu7.24, 2.20.11-0ubuntu27.18, 2.20.11-0ubuntu50.7, 2.20.11-0ubuntu65.1, and 2.14.1-0ubuntu3.29+esm7.

Understanding CVE-2021-20657

This section will provide insights into the nature and impact of the CVE-2021-20657 vulnerability.

What is CVE-2021-20657?

The vulnerability allowed malicious actors to inject modified package names through the 'get_modified_conffiles()' function, leading to confusion in calls to 'dpkg(1)'. This could potentially enable an attacker to execute arbitrary commands on the target system.

The Impact of CVE-2021-20657

With a CVSS score of 3.8, this low-severity vulnerability had a local attack vector and low confidentiality impact. However, if exploited, it could result in unauthorized command execution and system compromise.

Technical Details of CVE-2021-20657

Delve deeper into the technical aspects of CVE-2021-20657 to better understand its implications and significance.

Vulnerability Description

The vulnerability stemmed from improper input validation in the 'backends/packaging-apt-dpkg.py' script, allowing for the injection of malicious package names.

Affected Systems and Versions

The 'apport' package versions 2.20.1-0ubuntu2.30+esm1, 2.20.9-0ubuntu7.24, 2.20.11-0ubuntu27.18, 2.20.11-0ubuntu50.7, 2.20.11-0ubuntu65.1, and 2.14.1-0ubuntu3.29+esm7 were affected by this vulnerability.

Exploitation Mechanism

By leveraging the flaw in the 'get_modified_conffiles()' function, threat actors could manipulate package names to execute unauthorized commands through 'dpkg(1)', potentially leading to system compromise.

Mitigation and Prevention

Explore the recommended steps to mitigate the risks associated with CVE-2021-20657 and prevent exploitation of this vulnerability.

Immediate Steps to Take

Users are advised to update the 'apport' package to a non-vulnerable version. Additionally, security patches should be applied promptly to prevent exploitation.

Long-Term Security Practices

Implement secure coding practices, conduct regular security audits, and stay informed about security updates to mitigate the risk of similar vulnerabilities in the future.

Patching and Updates

Stay informed about security advisories and updates from Canonical to ensure that your systems are protected against known vulnerabilities.