CVE-2019-13233 : Security Advisory and Response

A vulnerability in the Linux kernel versions prior to 5.1.9, specifically in the file arch/x86/lib/insn-eval.c, allows unauthorized access to an LDT entry due to a race condition between modify_ldt() and a #BR exception.

Understanding CVE-2019-13233

This CVE refers to a use-after-free vulnerability in the Linux kernel.

What is CVE-2019-13233?

This vulnerability in the Linux kernel arises from a race condition between modify_ldt() and a #BR exception for an MPX bounds violation, leading to unauthorized access to an LDT entry.

The Impact of CVE-2019-13233

The vulnerability allows attackers to exploit a use-after-free scenario, potentially gaining unauthorized access to sensitive information within the affected systems.

Technical Details of CVE-2019-13233

This section provides more technical insights into the vulnerability.

Vulnerability Description

The issue occurs in arch/x86/lib/insn-eval.c in the Linux kernel before version 5.1.9, resulting in a use-after-free vulnerability for access to an LDT entry.

Affected Systems and Versions

Affected systems: Linux kernel versions prior to 5.1.9
Affected file: arch/x86/lib/insn-eval.c

Exploitation Mechanism

The vulnerability is exploited through a race condition between modify_ldt() and a #BR exception for an MPX bounds violation.

Mitigation and Prevention

Protecting systems from CVE-2019-13233 is crucial to maintaining security.

Immediate Steps to Take

Update the Linux kernel to version 5.1.9 or later to mitigate the vulnerability.
Monitor vendor advisories for patches and security updates.

Long-Term Security Practices

Regularly update and patch all software and systems to prevent known vulnerabilities.
Implement strong access controls and monitoring mechanisms to detect unauthorized access.

Patching and Updates

Apply patches provided by Linux kernel maintainers promptly to address the vulnerability.