CVE-2021-4197 : Vulnerability Insights and Analysis
Learn about CVE-2021-4197, a flaw in Linux kernel's control groups subsystem allowing local users to crash systems or escalate privileges. Find mitigation steps here.
This article provides details about CVE-2021-4197, a vulnerability in the Linux kernel's control groups and namespaces subsystem that could allow a local user to crash the system or escalate privileges.
Understanding CVE-2021-4197
CVE-2021-4197 is a vulnerability in the Linux kernel's control groups and namespaces subsystem, affecting the Linux kernel version 5.17-rc1.
What is CVE-2021-4197?
An unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces subsystem allows a local user to crash the system or escalate their privileges by accessing less privileged processes controlled by cgroups with a higher privileged parent process.
The Impact of CVE-2021-4197
The vulnerability could be exploited by a local user to disrupt the system's operation or elevate their privileges, posing a security risk to affected systems.
Technical Details of CVE-2021-4197
This section delves into the technical aspects of CVE-2021-4197, including its vulnerability description, affected systems and versions, and exploitation mechanism.
Vulnerability Description
The vulnerability stems from an unprivileged write to the file handler flaw in the Linux kernel's control groups and namespaces subsystem, affecting both cgroup1 and cgroup2 versions of control groups.
Affected Systems and Versions
The vulnerability affects systems running Linux kernel version 5.17-rc1.
Exploitation Mechanism
A local user can exploit this flaw to either crash the system or escalate their privileges by interacting with less privileged processes controlled by cgroups.
Mitigation and Prevention
In order to mitigate the risks associated with CVE-2021-4197, immediate steps should be taken along with the adoption of long-term security practices and keeping systems up to date with patches.
Immediate Steps to Take
Immediately apply patches provided by the respective vendors to address the vulnerability and prevent potential exploits.
Long-Term Security Practices
Enforce the principle of least privilege, regularly review access controls, and monitor system activity to enhance security posture.
Patching and Updates
Stay informed about security updates and regularly patch systems to protect against known vulnerabilities.