CVE-2023-34966

Description

An infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets sent by the client, the core unmarshalling function sl_unpack_loop() did not validate a field in the network packet that contains the count of elements in an array-like structure. By passing 0 as the count value, the attacked function will run in an endless loop consuming 100% CPU. This flaw allows an attacker to issue a malformed RPC request, triggering an infinite loop, resulting in a denial of service condition.

Statement

Red Hat has set this as Moderate severity issue, because this CVE only affects servers where Spotlight is explicitly enabled globally or on individual shares with "spotlight = yes". However, the default spotlight configuration is set as no - Check https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html#spotlight.

Mitigation

As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .

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 Score7.57.5N/A
Attack VectorNetworkNetworkN/A
Attack ComplexityLowLowN/A
Privileges RequiredNoneNoneN/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:N/UI:N/S:U/C:N/I:N/A:H

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

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Amplification

An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.

Frequently Asked Questions

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