CVE-2020-8694

Description

A flaw was found in the Linux kernel's implementation of Intel's Running Average Power Limit (RAPL) implementation. A local attacker could infer secrets by measuring power usage and also infer private data by observing the power usage of calculations performed on the data.

Mitigation

A temporary measure would be to remove the ability for non-root users
to read the current RAPL energy reporting metrics.

This can be done with the command:

$ sudo chmod 400 /sys/class/powercap/intel_rapl/*/energy_uj

This mitigation will only work on the current boot and will need to be reapplied at each system boot to remain in effect.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.55.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Understanding the Weakness (CWE)

Confidentiality,Integrity

Technical Impact: Read Application Data; Modify Application Data

Acknowledgements

Red Hat would like to thank Intel for reporting this issue.

Frequently Asked Questions

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