CVE-2023-54042

Description

A flaw was found in the Linux kernel on PowerPC 64-bit systems. In the Virtual Accelerator Switchboard (VAS) subsystem, the memory descriptor (mm) reference count is dropped before the coprocessor is properly detached. This ordering error can lead to a use-after-free condition when the mm structure is accessed after being freed.

Statement

This vulnerability is specific to PowerPC 64-bit server systems (powerpc/64s) using the VAS coprocessor interface. Most deployments on other architectures are not affected. The issue requires local access and use of VAS acceleration features, significantly limiting the attack surface.

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 Score4.7N/A7.8
Attack VectorLocalN/ALocal
Attack ComplexityHighN/ALow
Privileges RequiredLowN/ALow
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/AHigh
Integrity ImpactNoneN/AHigh
Availability ImpactHighN/AHigh

Vector

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

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

Understanding the Weakness (CWE)

Confidentiality

Technical Impact: Read Memory

If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Frequently Asked Questions

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