CVE-2021-20188 : Security Advisory and Response
Learn about CVE-2021-20188 affecting podman before 1.7.0. Understand the impact, affected systems, exploitation, and mitigation steps to protect your data and system integrity.
A security flaw was discovered in podman before version 1.7.0, where file permissions for non-root users in a privileged container are not adequately verified. This vulnerability could allow a low-privileged user within the container to access any file in the container, even those owned by the root user, compromising data confidentiality, integrity, and system availability.
Understanding CVE-2021-20188
This section will delve into the specifics of the CVE-2021-20188 vulnerability.
What is CVE-2021-20188?
The CVE-2021-20188 vulnerability is a file permission issue in podman before version 1.7.0 that could be exploited by a low-privileged user within a privileged container to access unauthorized files.
The Impact of CVE-2021-20188
The highest risk posed by CVE-2021-20188 is to data confidentiality and integrity, as well as system availability. Despite not allowing direct escape from the container, the flaw compromises security features when running the container.
Technical Details of CVE-2021-20188
In this section, we will explore the technical aspects of CVE-2021-20188 in more detail.
Vulnerability Description
The vulnerability arises from incorrect file permission checks for non-root users in privileged containers, enabling unauthorized access to files within the container.
Affected Systems and Versions
The affected product is 'podman' before version 1.7.0.
Exploitation Mechanism
A low-privileged user within a privileged container can exploit this vulnerability to access files owned by the root user in the container.
Mitigation and Prevention
This section provides guidance on mitigating the risks associated with CVE-2021-20188.
Immediate Steps to Take
Users are advised to update their podman installation to version 1.7.0 or later to address this vulnerability.
Long-Term Security Practices
It is recommended to follow best security practices such as running containers with non-root users and implementing least privilege access.
Patching and Updates
Regularly updating podman to the latest version can help prevent exploitation of known vulnerabilities.