CVE-2019-20428 : Security Advisory and Response

A vulnerability in the Lustre file system before version 2.12.3 could lead to an out-of-bounds read and panic due to insufficient validation of certain packet fields.

Understanding CVE-2019-20428

This CVE identifies a specific issue within the Lustre file system that could potentially result in a security breach.

What is CVE-2019-20428?

Prior to version 2.12.3 of Lustre, a flaw in the ptlrpc module allows for an out-of-bounds read and panic to occur. This vulnerability arises from the lack of validation for specific packet fields sent by a client. Additionally, the function ldl_request_cancel mishandles a large lock_count parameter.

The Impact of CVE-2019-20428

The vulnerability could be exploited by an attacker to trigger an out-of-bounds read and potentially cause a system panic, leading to a denial of service or other security issues.

Technical Details of CVE-2019-20428

This section delves into the technical aspects of the vulnerability.

Vulnerability Description

The issue lies within the ptlrpc module of the Lustre file system, where inadequate validation of certain packet fields can result in an out-of-bounds read and panic. The mishandling of a large lock_count parameter in the ldl_request_cancel function further exacerbates the vulnerability.

Affected Systems and Versions

Systems running Lustre file system versions prior to 2.12.3 are vulnerable.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted packets with manipulated fields to trigger the out-of-bounds read and panic.

Mitigation and Prevention

Protecting systems from CVE-2019-20428 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Lustre file system to version 2.12.3 or later to mitigate the vulnerability.
Monitor network traffic for any suspicious activity that could indicate exploitation of this issue.

Long-Term Security Practices

Regularly update and patch all software components to prevent known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

Apply patches provided by Lustre to address the vulnerability and enhance system security.