CVE-2021-21781 Explained : Impact and Mitigation
Explore the details of CVE-2021-21781, an information disclosure vulnerability in Linux Kernel versions 5.4.54 and 5.4.66. Learn about its impact, affected systems, exploitation mechanism, and mitigation steps.
This CVE-2021-21781 article provides insights into an information disclosure vulnerability existing in the ARM SIGPAGE functionality of Linux Kernel versions 5.4.54 and 5.4.66.
Understanding CVE-2021-21781
This section delves into the details of CVE-2021-21781, shedding light on the impact, technical aspects, and mitigation strategies.
What is CVE-2021-21781?
CVE-2021-21781 is an information disclosure vulnerability in the ARM SIGPAGE functionality of Linux Kernel versions 5.4.54 and 5.4.66. It allows a userland application to access the sigpage contents, potentially leaking kernel memory data.
The Impact of CVE-2021-21781
The vulnerability's impact is rated as medium severity with a CVSS base score of 4. Since the latest version (5.11-rc4) remains vulnerable, attackers can exploit this flaw to read a process's memory at a specific offset.
Technical Details of CVE-2021-21781
Explore the technical specifics of the CVE-2021-21781 vulnerability, including the description, affected systems, versions, and exploitation mechanism.
Vulnerability Description
The vulnerability allows unauthorized access to kernel memory through the sigpage, posing a risk of information disclosure by reading process memory at a specified offset.
Affected Systems and Versions
Linux Kernel versions 5.4.54 and 5.4.66 are impacted by this vulnerability, potentially exposing sensitive kernel memory content to unauthorized users.
Exploitation Mechanism
By leveraging a userland application, attackers can exploit this flaw to read kernel memory contents at a specific offset, leading to information disclosure.
Mitigation and Prevention
Discover the steps to mitigate the risks associated with CVE-2021-21781 and prevent potential attacks.
Immediate Steps to Take
To mitigate the vulnerability, users are advised to update their systems to the patched kernel releases, including versions 4.14.222, 4.19.177, 5.4.99, 5.10.17, and 5.11.
Long-Term Security Practices
Implement robust security practices, such as regular security audits, access control measures, and privilege separation, to enhance overall system security.
Patching and Updates
Regularly apply security patches provided by Linux Kernel developers to address known vulnerabilities and strengthen the security posture of the system.