CVE-2021-29650 : What You Need to Know

An issue was discovered in the Linux kernel before 5.11.11, where the netfilter subsystem allows attackers to cause a denial of service (panic) due to a lack of a full memory barrier upon assigning a new table value.

Understanding CVE-2021-29650

This CVE describes a vulnerability in the Linux kernel that can be exploited by attackers to trigger a denial of service attack.

What is CVE-2021-29650?

CVE-2021-29650 is a vulnerability identified in the Linux kernel versions prior to 5.11.11. It stems from insufficient memory barrier checks during the assignment of new table values in the netfilter subsystem.

The Impact of CVE-2021-29650

The vulnerability can be exploited by malicious actors to induce a denial of service (DoS) condition on affected systems, potentially leading to system crashes or unresponsiveness.

Technical Details of CVE-2021-29650

This section delves into the specifics of the vulnerability, outlining the affected systems, exploitation mechanism, and recommended mitigation strategies.

Vulnerability Description

The issue is rooted in the lack of adequate memory barrier verification during the assignment of new table values in the netfilter subsystem, enabling attackers to trigger a panic and disrupt system operations.

Affected Systems and Versions

Linux kernel versions before 5.11.11 are susceptible to this vulnerability if they utilize the netfilter subsystem. Systems running on these versions may be at risk of a DoS attack.

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating the assignment of table values in the netfilter subsystem, causing a panic and leading to system instability.

Mitigation and Prevention

To safeguard systems from potential exploitation, immediate steps and long-term security practices need to be implemented alongside system patching and updates.

Immediate Steps to Take

System administrators are advised to monitor security advisories, apply relevant patches promptly, and employ network-level mitigations to prevent possible attacks exploiting this vulnerability.

Long-Term Security Practices

In the long run, organizations should prioritize regular security assessments, implement defense-in-depth strategies, and ensure comprehensive security measures are in place to mitigate similar vulnerabilities.

Patching and Updates

Regularly updating the Linux kernel to versions 5.11.11 and above that address this vulnerability is crucial. Organizations should maintain a proactive approach to applying patches and staying informed about security developments.