CVE-2023-42670

Description

A flaw was found in Samba. It is susceptible to a vulnerability where multiple incompatible RPC listeners can be initiated, causing disruptions in the AD DC service. When Samba's RPC server experiences a high load or unresponsiveness, servers intended for non-AD DC purposes (for example, NT4-emulation "classic DCs") can erroneously start and compete for the same unix domain sockets. This issue leads to partial query responses from the AD DC, causing issues such as "The procedure number is out of range" when using tools like Active Directory Users. This flaw allows an attacker to disrupt AD DC services.

Statement

The Samba package as shipped with Red Hat Enterprise Linux 6, 7, 8 and 9 and Red Hat Gluster Storage is not affected by this issue as Red Hat doesn't provide the AD Domain Controller capability with it.

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)

Availability

Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)

If an attacker can trigger the allocation of the limited resources, but the number or size of the resources is not controlled, then the most common result is denial of service. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment, i.e., the product may slow down, crash due to unhandled errors, or lock out legitimate users. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system.

Access Control,Other

Technical Impact: Bypass Protection Mechanism; Other

In some cases it may be possible to force the product to "fail open" in the event of resource exhaustion. The state of the product -- and possibly the security functionality - may then be compromised.

Frequently Asked Questions

Want to get errata notifications? Sign up here.