CVE-2020-14383

Description

A flaw was found in Samba's DNS server. This flaw allows an authenticated user to crash the RPC server. The RPC server, which also serves protocols other than the DNS server, is restarted after a short delay, however, an authenticated non-administrative attacker can cause a crash as soon as it returns. The Samba DNS server continues to operate, but many RPC services do not. The highest threat from this vulnerability is system availability.

Statement

This issue does not affect the version of samba as shipped with Red Hat Enterprise Linux 6, 7, 8 and Red Hat Gluster Storage 3 as it does not include support for Active Directory Domain Controller.

Mitigation

The dnsserver task can be stopped by setting

 'dcerpc endpoint servers = -dnsserver'

in the smb.conf and restarting Samba.

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 Score6.56.5N/A
Attack VectorNetworkNetworkN/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:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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

Understanding the Weakness (CWE)

Integrity,Other

Technical Impact: Varies by Context; Unexpected State; Alter Execution Logic

Acknowledgements

Red Hat would like to thank the Samba project for reporting this issue. Upstream acknowledges Francis Brosnan Blázquez (ASPL.es) as the original reporter.

Frequently Asked Questions

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