Linux Kernel up to 4.8.10 Performance Monitor sys_regs.c access_pmu_evcntr input validation

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 4.8.10. Affected by this vulnerability is the function access_pmu_evcntr of the file arch/arm64/kvm/sys_regs.c of the component Performance Monitor. Executing a manipulation can lead to input validation. This vulnerability is handled as CVE-2017-12168. It is possible to launch the attack on the local host. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 4.8.10 (Operating System). This vulnerability affects the function access_pmu_evcntr of the file arch/arm64/kvm/sys_regs.c of the component Performance Monitor. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability. CVE summarizes:

The access_pmu_evcntr function in arch/arm64/kvm/sys_regs.c in the Linux kernel before 4.8.11 allows privileged KVM guest OS users to cause a denial of service (assertion failure and host OS crash) by accessing the Performance Monitors Cycle Count Register (PMCCNTR).

The bug was discovered 09/19/2017. The weakness was released 09/20/2017 as confirmed git commit (GIT Repository). The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2017-12168 since 08/01/2017. The exploitation appears to be easy. The attack needs to be approached locally. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 4.8.11 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be patching the affected component.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.8.0
• 4.8.1
• 4.8.2
• 4.8.3
• 4.8.4
• 4.8.5
• 4.8.6
• 4.8.7
• 4.8.8
• 4.8.9
• 4.8.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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