CVE-2021-38206 Explained : Impact and Mitigation
Learn about CVE-2021-38206, a denial of service vulnerability in the Linux kernel, allowing attackers to exploit a NULL pointer dereference in the mac80211 subsystem.
A denial of service vulnerability (NULL pointer dereference) in the mac80211 subsystem of the Linux kernel before version 5.12.13 can be exploited by injecting a frame with 802.11a rates when a device supporting only 5 GHz is used.
Understanding CVE-2021-38206
This section provides insights into the nature and impact of CVE-2021-38206.
What is CVE-2021-38206?
The CVE-2021-38206 vulnerability affects the mac80211 subsystem in the Linux kernel, allowing attackers to trigger a denial of service by exploiting a NULL pointer dereference in the radiotap parser.
The Impact of CVE-2021-38206
By injecting a frame with 802.11a rates on devices that support only 5 GHz, attackers can cause a denial of service within affected systems.
Technical Details of CVE-2021-38206
Explore the specific technical aspects of CVE-2021-38206 in this section.
Vulnerability Description
The vulnerability stems from improper handling of 802.11a rates within the mac80211 subsystem, leading to a NULL pointer dereference in the radiotap parser.
Affected Systems and Versions
The Linux kernel versions prior to 5.12.13 are vulnerable to CVE-2021-38206 when used with devices that operate exclusively on 5 GHz frequencies.
Exploitation Mechanism
Exploiting this vulnerability involves injecting a frame with specified 802.11a rates to trigger the NULL pointer dereference and initiate a denial of service attack.
Mitigation and Prevention
Discover the measures to mitigate and prevent the exploitation of CVE-2021-38206 in this section.
Immediate Steps to Take
Immediately upgrading to Linux kernel version 5.12.13 or higher can help mitigate the risk of exploitation associated with this vulnerability.
Long-Term Security Practices
Implementing regular security updates and staying informed about kernel patches can enhance long-term security posture against potential vulnerabilities.
Patching and Updates
Timely application of security patches released by the Linux kernel maintainers is crucial to address known vulnerabilities like CVE-2021-38206.