CVE-2018-10906 Explained : Impact and Mitigation

CVE-2018-10906 was published on July 24, 2018, and affects versions of fuse prior to 2.9.8 and 3.x before 3.2.5. This vulnerability allows non-root users to bypass restrictions when SELinux is enabled, potentially leading to Denial of Service or other consequences.

Understanding CVE-2018-10906

This CVE entry highlights a vulnerability in the fusermount component of fuse that enables non-root users to mount a FUSE file system with certain permissions, even when SELinux is active.

What is CVE-2018-10906?

In versions of fuse before 2.9.8 and 3.x before 3.2.5, a flaw in fusermount allows non-root users to mount a FUSE file system with the 'allow_other' mount option, regardless of the 'user_allow_other' setting in the fuse configuration.

The Impact of CVE-2018-10906

Exploiting this vulnerability could permit an attacker to mount a FUSE file system accessible to other users, potentially leading to unauthorized access and manipulation of files, resulting in Denial of Service or other unknown outcomes.

Technical Details of CVE-2018-10906

This section delves into the specifics of the vulnerability.

Vulnerability Description

The vulnerability in fusermount allows non-root users to mount FUSE file systems with elevated permissions, bypassing restrictions imposed by SELinux.

Affected Systems and Versions

Product: fuse
Versions: 2.9.8 and 3.2.5

Exploitation Mechanism

Non-root users can exploit this vulnerability to mount FUSE file systems with the 'allow_other' option, circumventing SELinux restrictions.

Mitigation and Prevention

To address CVE-2018-10906, consider the following mitigation strategies:

Immediate Steps to Take

Update fuse to version 2.9.8 or 3.2.5 to mitigate the vulnerability.
Implement SELinux policies to restrict unauthorized access.

Long-Term Security Practices

Regularly update software and apply security patches.
Enforce the principle of least privilege to limit user permissions.

Patching and Updates

Stay informed about security advisories and promptly apply patches to vulnerable systems.