CVE-2023-28642 : Vulnerability Insights and Analysis

This CVE, assigned on March 20, 2023, and published on March 29, 2023, highlights a vulnerability that allows AppArmor to be bypassed when

/proc

inside a container is symlinked with a specific mount configuration in the runc CLI tool for containers according to the OCI specification.

Understanding CVE-2023-28642

This section delves into the details and impact of the CVE-2023-28642 vulnerability.

What is CVE-2023-28642?

CVE-2023-28642 is a vulnerability in the runc CLI tool where AppArmor protection can be bypassed through a specific symlink configuration within the container, potentially exposing the system to security risks.

The Impact of CVE-2023-28642

The impact of this vulnerability is rated as medium with a CVSS v3.1 base score of 6.1. Attack complexity is considered low, requiring local access and user interaction. While the confidentiality and integrity impacts are low, it can lead to a change in scope and availability.

Technical Details of CVE-2023-28642

In this section, we will explore the vulnerability description, affected systems and versions, as well as the exploitation mechanism.

Vulnerability Description

The vulnerability in runc allows for the bypassing of AppArmor protection by creating a symlink between

/proc

inside the container with a specific mount configuration. This issue has been addressed in runc version 1.1.5 by disallowing symlinked

/proc

.

Affected Systems and Versions

The affected product is 'runc' by opencontainers with versions below 1.1.5 being vulnerable to this exploit.

Exploitation Mechanism

To exploit this vulnerability, an attacker needs to symlink

/proc

within the container with a specific mount configuration, thereby bypassing AppArmor protection.

Mitigation and Prevention

In this section, we will discuss immediate steps to take, long-term security practices, and the importance of patching and updates.

Immediate Steps to Take

Users are strongly advised to upgrade runc to version 1.1.5 or above to mitigate this vulnerability. For users unable to upgrade immediately, it is recommended to avoid using untrusted container images that could potentially exploit this issue.

Long-Term Security Practices

To enhance container security in the long term, it is crucial to regularly update container runtimes and implement secure configurations to prevent similar vulnerabilities from being exploited in the future.

Patching and Updates

Regularly monitor for security updates from the runc project and apply patches promptly to ensure that your containerized environments remain secure and protected against known vulnerabilities.