CVE-2023-4273

Description

A flaw was found in the exFAT driver of the Linux kernel. The vulnerability exists in the implementation of the file name reconstruction function, which is responsible for reading file name entries from a directory index and merging file name parts belonging to one file into a single long file name. Since the file name characters are copied into a stack variable, a local privileged attacker could use this flaw to overflow the kernel stack.

Statement

Red Hat Enterprise Linux 6, 7 and 8 are not affected by this flaw as they did not include exFAT filesystem support (introduced upstream in kernel v5.7).

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 Score66.7N/A
Attack VectorLocalLocalN/A
Attack ComplexityLowLowN/A
Privileges RequiredHighHighN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityHighHighN/A
Integrity ImpactHighHighN/A
Availability ImpactNoneHighN/A

Vector

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

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

Understanding the Weakness (CWE)

Availability

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

Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Integrity,Confidentiality,Availability,Access Control

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism

Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy.

Integrity,Confidentiality,Availability,Access Control,Other

Technical Impact: Modify Memory; Execute Unauthorized Code or Commands; Bypass Protection Mechanism; Other

When the consequence is arbitrary code execution, this can often be used to subvert any other security service.

Acknowledgements

Red Hat would like to thank Maxim Suhanov for reporting this issue.

Frequently Asked Questions

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