CVE-2019-20485 : What You Need to Know

In versions of libvirt prior to 6.0.0, a flaw in the handling of a monitor job in qemu/qemu_driver.c can be exploited by attackers to trigger a denial of service, leading to API blockage.

Understanding CVE-2019-20485

In this CVE, a vulnerability in libvirt's handling of monitor jobs can result in a denial of service attack.

What is CVE-2019-20485?

This CVE pertains to a flaw in the qemu/qemu_driver.c file in libvirt versions before 6.0.0. The issue arises when a query is made to a guest agent, allowing attackers to exploit this flaw for a denial of service attack, effectively blocking the API.

The Impact of CVE-2019-20485

The vulnerability can be leveraged by malicious actors to disrupt services, causing denial of service and potentially impacting the availability of the API.

Technical Details of CVE-2019-20485

This section delves into the technical aspects of the CVE.

Vulnerability Description

The flaw in qemu/qemu_driver.c mishandles the holding of a monitor job during a query to a guest agent, enabling attackers to cause a denial of service by blocking the API.

Affected Systems and Versions

Affected versions: libvirt versions prior to 6.0.0

Exploitation Mechanism

Attackers can exploit this vulnerability by triggering a denial of service attack, leading to the blocking of the API.

Mitigation and Prevention

Protecting systems from CVE-2019-20485 involves taking immediate steps and implementing long-term security practices.

Immediate Steps to Take

Update libvirt to version 6.0.0 or newer to mitigate the vulnerability
Monitor for any unusual API blockages or denial of service attempts

Long-Term Security Practices

Regularly update software and apply patches promptly
Conduct security assessments and audits to identify and address vulnerabilities

Patching and Updates

Apply patches provided by libvirt to address the flaw and enhance system security