CVE-2026-46139

Description

A flaw was found in the Linux kernel's Server Message Block (SMB) client. When building an Access Control List (ACL) descriptor, a buffer was not properly zero-initialized, leaving a reserved field with uninitialized heap data. This can lead to Samba rejecting the security descriptor, causing chmod operations to fail with an invalid argument error. This issue can result in a Denial of Service (DoS) for affected file system operations.

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 Score75.5N/A
Attack VectorLocalLocalN/A
Attack ComplexityHighLowN/A
Privileges RequiredLowLowN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighNoneN/A
Integrity ImpactHighNoneN/A
Availability ImpactHighHighN/A

Vector

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

CWE-909

Confidentiality

Technical Impact: Read Memory; Read Application Data

When reusing a resource such as memory or a program variable, the original contents of that resource may not be cleared before it is sent to an untrusted party.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

The uninitialized resource may contain values that cause program flow to change in ways that the programmer did not intend.

Frequently Asked Questions

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