CVE-2019-15031 Explained : Impact and Mitigation

A security issue has been identified in the Linux kernel versions up to 5.2.14 on the powerpc platform, allowing a local user to gain unauthorized access to other users' vector registers.

Understanding CVE-2019-15031

This CVE involves a vulnerability in the Linux kernel that can be exploited by a local user to access vector registers of other users' processes.

What is CVE-2019-15031?

The vulnerability allows a local user to gain unauthorized access to vector registers of other users' processes on the powerpc platform.
By utilizing an interrupt, a local user can initiate a transaction using the tbegin instruction in hardware transactional memory, followed by accessing the vector registers.
Due to incorrect usage of MSR_TM_ACTIVE in the arch/powerpc/kernel/process.c file, vector registers can become corrupted with values from a different local Linux process.

The Impact of CVE-2019-15031

Unauthorized access to vector registers can lead to potential information disclosure and privilege escalation within the affected system.

Technical Details of CVE-2019-15031

This section provides detailed technical information about the CVE.

Vulnerability Description

The vulnerability in the Linux kernel allows a local user to read vector registers of other users' processes via an interrupt.
By starting a transaction with the tbegin instruction and accessing vector registers, the registers can be corrupted with values from a different local Linux process.

Affected Systems and Versions

Linux kernel versions up to 5.2.14 on the powerpc platform are affected by this vulnerability.

Exploitation Mechanism

The vulnerability is exploited by a local user initiating a transaction using the tbegin instruction in hardware transactional memory and accessing vector registers.

Mitigation and Prevention

Protecting systems from CVE-2019-15031 is crucial to maintaining security.

Immediate Steps to Take

Apply patches provided by the Linux kernel to address the vulnerability.
Monitor system logs for any unusual activities that may indicate exploitation attempts.

Long-Term Security Practices

Implement the principle of least privilege to restrict user access to sensitive resources.
Regularly update and patch the system to prevent known vulnerabilities from being exploited.

Patching and Updates

Stay informed about security updates and patches released by the Linux kernel community to address vulnerabilities like CVE-2019-15031.