CVE-2022-41222

Description

A use-after-free flaw was found in the Linux kernel’s mm/mremap memory address space accounting source code in how a race condition happens between rmap walk and mremap. This flaw allows a local user to crash or potentially escalate their privileges on the system.

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 Score777
Attack VectorLocalLocalLocal
Attack ComplexityHighHighHigh
Privileges RequiredLowLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactHighHighHigh
Availability ImpactHighHighHigh

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:H/PR:L/UI:N/S:U/C:H/I:H/A:H

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

Red Hat CVSS v3 Score Explanation

The bug allows to read freed memory, so potentially possible to get unauthorized access to some important data from memory that could help to escalate privileges. The AC:H, because both race condition should happen and lucky enough to find something important in just freed memory.

Understanding the Weakness (CWE)

Integrity

Technical Impact: Modify Memory

The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.

Availability

Technical Impact: DoS: Crash, Exit, or Restart

If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.

Confidentiality

Technical Impact: Read Memory

Read operations on freed memory can sometimes leak sensitive information instead of causing a crash

Integrity,Confidentiality,Availability

Technical Impact: Execute Unauthorized Code or Commands

If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Frequently Asked Questions

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