CVE-2019-13648 : Security Advisory and Response

In the Linux kernel version 5.2.1 and earlier on the powerpc platform, a vulnerability exists that allows a local user to cause a denial of service attack by exploiting the absence of hardware transactional memory.

Understanding CVE-2019-13648

This CVE entry describes a specific vulnerability in the Linux kernel affecting the powerpc platform.

What is CVE-2019-13648?

CVE-2019-13648 is a vulnerability in the Linux kernel that enables a local user to trigger a denial of service attack by utilizing a specially crafted signal frame through a sigreturn() system call.

The Impact of CVE-2019-13648

The vulnerability results in a TM Bad Thing exception being raised, leading to a system crash on the affected powerpc platform running Linux kernel versions 5.2.1 and earlier.

Technical Details of CVE-2019-13648

This section provides more in-depth technical details about the vulnerability.

Vulnerability Description

The issue arises when hardware transactional memory is disabled on the powerpc platform, allowing a local user to exploit the kernel through a crafted signal frame.

Affected Systems and Versions

Linux kernel versions 5.2.1 and earlier on the powerpc platform
Specifically impacts the files signal_32.c and signal_64.c in the arch/powerpc/kernel directory

Exploitation Mechanism

Local user triggers a denial of service attack by using a specially crafted signal frame
Exploited through the sigreturn() system call

Mitigation and Prevention

Protecting systems from CVE-2019-13648 involves taking immediate steps and implementing long-term security practices.

Immediate Steps to Take

Apply relevant security updates and patches promptly
Monitor for any unusual system crashes or exceptions

Long-Term Security Practices

Regularly update the Linux kernel to the latest stable version
Implement proper access controls and user permissions

Patching and Updates

Refer to official vendor advisories and security updates for patching guidance