CVE-2021-47412

Description

A vulnerability was found in the Linux kernel, where improper handling of block I/O requests when a block I/O request (bio) is not tracked, the kernel erroneously calls the rq_qos_ops->done_bio function, potentially leading to use-after-free issues. This situation can occurr when the request queue is accessed after it has been freed, resulting in possible kernel panic.

Statement

This vulnerability is classified as moderate severity, as the issue can cause kernel panics, leading to system crashes. However, it does not affect data confidentiality or integrity.

Mitigation

Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.

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 Score4.75.57.8
Attack VectorLocalLocalLocal
Attack ComplexityHighLowLow
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityNoneNoneHigh
Integrity ImpactNoneNoneHigh
Availability ImpactHighHighHigh

Vector

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

NVD: CVSS:3.1/AV:L/AC:L/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)

Integrity,Confidentiality,Availability

Technical Impact: Modify Application Data; Modify Memory; DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands

It may be possible to cause data corruption and possibly execute arbitrary code by modifying global variables or data structures at unexpected times, violating the assumptions of code that uses this global data.

Access Control

Technical Impact: Gain Privileges or Assume Identity

If a signal handler interrupts code that is executing with privileges, it may be possible that the signal handler will also be executed with elevated privileges, possibly making subsequent exploits more severe.

Frequently Asked Questions

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