CVE-2024-49991

Description

A flaw was found in the Linux kernel's drm/amdkfd component. This use-after-free vulnerability occurs in the amdkfd_free_gtt_mem function due to incorrect pointer handling. An attacker with administrative privileges could exploit this flaw, potentially leading to information disclosure or a denial of service.

Statement

This issue is considered to be a moderate impact flaw, as the exploitation for this will need an ADMIN (or ROOT) privilege (PR:H).

Mitigation

To mitigate this issue, the `amdkfd` kernel module can be blacklisted to prevent it from loading. This action may impact systems utilizing AMD GPUs that rely on this module for functionality.

To blacklist the module, create a file named `/etc/modprobe.d/amdkfd-blacklist.conf` with the following content:

blacklist amdkfd

After creating the file, regenerate the initramfs and reboot the system for the changes to take effect:

bash
dracut -f
# OR (for older systems)
mkinitrd -f
reboot

A system reboot is required for the changes to take effect.

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 Score67.87.8
Attack VectorLocalLocalLocal
Attack ComplexityLowLowLow
Privileges RequiredHighLowLow
User InteractionNoneNoneNone
ScopeUnchangedUnchangedUnchanged
ConfidentialityHighHighHigh
Integrity ImpactNoneHighHigh
Availability ImpactHighHighHigh

Vector

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

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

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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