CVE-2020-36322

Description

A denial of service flaw was found in fuse_do_getattr in fs/fuse/dir.c in the kernel side of the FUSE filesystem in the Linux kernel. A local user could use this flaw to crash the system.

Statement

This issue affected Linux kernel versions as shipped with Red Hat Enterprise Linux from 8.3 and prior the versions. RHEL 8.4 and later versions are not affected.

Mitigation

As the FUSE module will be auto-loaded when required, its use can be disabled by preventing the module from loading with the following instructions:

# echo "install fuse /bin/true" >> /etc/modprobe.d/disable-fuse.conf

The system will need to be restarted if the FUSE modules are loaded. In most circumstances, the CIFS kernel modules will be unable to be unloaded while the FUSE filesystems are in use.

If the system requires this module to work correctly, this mitigation may not be suitable.

If you need further assistance, see KCS article https://access.redhat.com/solutions/41278 or contact Red Hat Global Support Services.

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 Score5.55.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneNoneN/A
Integrity ImpactNoneNoneN/A
Availability ImpactHighHighN/A

Vector

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

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

Understanding the Weakness (CWE)

Other,Confidentiality,Integrity

Technical Impact: Other; Read Application Data; Modify Application Data; DoS: Resource Consumption (Other)

It is possible to overflow the number of temporary files because directories typically have limits on the number of files allowed. This could create a denial of service problem.

Frequently Asked Questions

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