CVE-2019-14835 : What You Need to Know

Researchers have identified a vulnerability in the Linux kernel versions 2.6.34 to 5.2.x related to the vhost functionality, allowing a guest user to elevate privileges on the host system.

Understanding CVE-2019-14835

This CVE involves a flaw in the Linux kernel's vhost functionality that can be exploited by a guest user with privileged access to escalate their privileges on the host system.

What is CVE-2019-14835?

The vulnerability in the Linux kernel, specifically versions 2.6.34 to 5.2.x, is associated with the vhost functionality responsible for converting virtqueue buffers to IOVs. The issue arises during the migration process when buffer descriptors are improperly handled, enabling a guest user to pass descriptors with an invalid length to the host and gain elevated privileges.

The Impact of CVE-2019-14835

The impact of this vulnerability is rated as HIGH, with a CVSS base score of 7.2. The attack complexity is considered HIGH, requiring local access and user interaction. Successful exploitation can result in a significant impact on confidentiality, integrity, and availability of the affected system.

Technical Details of CVE-2019-14835

The technical details of CVE-2019-14835 provide insight into the vulnerability's description, affected systems, and exploitation mechanism.

Vulnerability Description

The vulnerability allows a guest user with privileged access to exploit the vhost functionality in the Linux kernel versions 2.6.34 to 5.2.x during the migration process, leading to privilege escalation on the host system.

Affected Systems and Versions

Product: Linux kernel
Vendor: Linux Kernel
Versions affected: from version 2.6.34 to 5.2.x

Exploitation Mechanism

The flaw involves passing descriptors with an invalid length from the guest to the host during the migration process, enabling the guest user to elevate their privileges on the host system.

Mitigation and Prevention

To address CVE-2019-14835, immediate steps should be taken to mitigate the risk and prevent potential exploitation.

Immediate Steps to Take

Apply security patches provided by the vendor promptly.
Monitor vendor advisories and security mailing lists for updates.
Restrict guest user privileges to minimize the impact of potential exploitation.

Long-Term Security Practices

Implement least privilege access controls to limit user capabilities.
Regularly update and patch the Linux kernel to address known vulnerabilities.
Conduct security assessments and audits to identify and remediate potential risks.

Patching and Updates

Refer to vendor-specific security advisories for patch availability and installation instructions.
Keep systems up to date with the latest security patches to mitigate known vulnerabilities effectively.