CVE-2017-12168 : Security Advisory and Response

CVE-2017-12168 pertains to a vulnerability in the Linux kernel before version 4.9 that allows privileged users of KVM guest operating systems to trigger a denial of service attack by accessing the Performance Monitors Cycle Count Register (PMCCNTR).

Understanding CVE-2017-12168

This CVE entry highlights a security flaw in the arm64 architecture of the Linux kernel that can lead to a host operating system crash.

What is CVE-2017-12168?

The access_pmu_evcntr function in the sys_regs.c file of the Linux kernel before version 4.8.11 enables privileged users to exploit the PMCCNTR, causing a denial of service attack.

The Impact of CVE-2017-12168

Exploiting this vulnerability can result in an assertion failure, leading to a crash of the host operating system.

Technical Details of CVE-2017-12168

This section delves into the specifics of the vulnerability.

Vulnerability Description

The flaw allows privileged users of KVM guest operating systems to trigger a denial of service attack by accessing the PMCCNTR.

Affected Systems and Versions

Product: Linux kernel before 4.9
Versions: Linux kernel before 4.9

Exploitation Mechanism

The vulnerability is exploited by gaining access to the PMCCNTR, ultimately causing a denial of service attack.

Mitigation and Prevention

Protecting systems from CVE-2017-12168 involves taking immediate and long-term security measures.

Immediate Steps to Take

Apply relevant patches and updates to the Linux kernel.
Monitor system logs for any suspicious activities.

Long-Term Security Practices

Implement least privilege access controls.
Regularly update and patch the operating system and software.

Patching and Updates

Ensure that the Linux kernel is updated to version 4.9 or newer to mitigate the vulnerability.