CVE-2020-10717 : Vulnerability Insights and Analysis

A potential DoS flaw in the virtio-fs shared file system daemon (virtiofsd) implementation of QEMU version >= v5.0 allows a guest user to cause a denial of service on the host.

Understanding CVE-2020-10717

This CVE identifies a vulnerability in the QEMU virtualization software.

What is CVE-2020-10717?

The vulnerability lies in the virtio-fs shared file system daemon (virtiofsd) of QEMU version >= v5.0.
It enables a guest user/process to trigger a denial of service on the host by opening the maximum number of file descriptors under a shared directory.

The Impact of CVE-2020-10717

CVSS Score: 3.3 (Low)
Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Confidentiality Impact: None
Integrity Impact: None
Availability Impact: Low
This vulnerability's exploitation could lead to a denial of service on the host system.

Technical Details of CVE-2020-10717

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The flaw in virtio-fs allows a guest user to exhaust file descriptors, causing a denial of service on the host.

Affected Systems and Versions

Vendor: The QEMU Project
Product: QEMU
Affected Versions: >= QEMU v5.0

Exploitation Mechanism

By opening the maximum number of file descriptors under a shared directory, a guest user/process can trigger the denial of service on the host.

Mitigation and Prevention

Protecting systems from CVE-2020-10717 requires immediate actions and long-term security practices.

Immediate Steps to Take

Apply vendor patches or updates promptly.
Monitor and limit the number of file descriptors a guest can open.

Long-Term Security Practices

Regularly update and patch virtualization software.
Implement proper access controls and restrictions on guest activities.

Patching and Updates

Ensure QEMU software is updated to a version that includes a fix for CVE-2020-10717.