CVE-2021-3631

Description

A flaw was found in libvirt while it generates SELinux MCS category pairs for VMs' dynamic labels. This flaw allows one exploited guest to access files labeled for another guest, resulting in the breaking out of sVirt confinement. The highest threat from this vulnerability is to confidentiality and integrity.

Statement

This flaw affects all versions of libvirt as shipped with Red Hat Enterprise Linux 8 and Red Hat Enterprise Linux 8 Advanced Virtualization. A future update may address this issue.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

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).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score36.3N/A
Attack VectorLocalLocalN/A
Attack ComplexityHighHighN/A
Privileges RequiredHighLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityLowHighN/A
Integrity ImpactLowHighN/A
Availability ImpactNoneNoneN/A

Vector

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

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

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Application Data; Read Files or Directories

An attacker may be able to read sensitive information from the associated resource, such as credentials or configuration information stored in a file.

Access Control

Technical Impact: Gain Privileges or Assume Identity

An attacker may be able to modify critical properties of the associated resource to gain privileges, such as replacing a world-writable executable with a Trojan horse.

Integrity,Other

Technical Impact: Modify Application Data; Other

An attacker may be able to destroy or corrupt critical data in the associated resource, such as deletion of records from a database.

Frequently Asked Questions

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