CVE-2021-28950 : What You Need to Know

An issue was discovered in fs/fuse/fuse_i.h in the Linux kernel before 5.11.8. A 'stall on CPU' can occur because a retry loop continually finds the same bad inode, aka CID-775c5033a0d1.

Understanding CVE-2021-28950

This CVE highlights a vulnerability in the Linux kernel prior to version 5.11.8 that can lead to a 'stall on CPU.'

What is CVE-2021-28950?

CVE-2021-28950 points out an issue in fs/fuse/fuse_i.h in the Linux kernel, causing a loop to repeatedly discover the same bad inode, potentially leading to a CPU stall.

The Impact of CVE-2021-28950

The impact of this CVE is the possibility of a CPU stall due to the identified retry loop finding the same problematic inode continuously.

Technical Details of CVE-2021-28950

The technical details of this CVE include the vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The vulnerability lies within fs/fuse/fuse_i.h in the Linux kernel before version 5.11.8, resulting in a loop that fails to progress beyond a bad inode, causing a CPU stall.

Affected Systems and Versions

Systems running Linux kernel versions before 5.11.8 are affected by this vulnerability, potentially leading to a CPU stall scenario.

Exploitation Mechanism

The exploitation of this CVE involves triggering the retry loop in fs/fuse/fuse_i.h to continuously encounter the same bad inode, resulting in a 'stall on CPU.'

Mitigation and Prevention

To mitigate and prevent the risks associated with CVE-2021-28950, immediate steps and long-term security practices are crucial.

Immediate Steps to Take

Immediate steps include monitoring for security updates related to the Linux kernel and applying patches promptly to prevent any potential CPU stall incidents.

Long-Term Security Practices

Establishing robust security protocols, staying informed about kernel updates, and maintaining a proactive approach to system security are essential for long-term protection.

Patching and Updates

Regularly checking for Linux kernel updates, particularly versions beyond 5.11.8, and promptly applying patches can safeguard systems from the vulnerability identified in CVE-2021-28950.