CVE-2026-43206
Description
A flaw was found in the Linux kernel's drm/amdkfd component. An unprivileged local user can exploit an out-of-bounds write vulnerability in the kfd_event_page_set() function. This occurs because the function writes data without properly validating the buffer size, allowing a small buffer to trigger a write beyond its allocated memory. Successful exploitation of this flaw could lead to potential privilege escalation.
Statement
This Important vulnerability in the drm/amdkfd kernel module allows an unprivileged local attacker to trigger an out-of-bounds write, potentially leading to privilege escalation. Systems running Red Hat Enterprise Linux with AMD graphics drivers are affected.
Mitigation
To mitigate this issue, prevent the `amdkfd` kernel module from loading if it is not required. This can be achieved by blacklisting the module.
1. Create a new file `/etc/modprobe.d/blacklist-amdkfd.conf` with the following content:
`blacklist amdkfd`
2. Regenerate the initramfs to ensure the blacklist is applied during boot:
`sudo dracut -f -v` (for RHEL 8/9)
`sudo mkinitrd -f -v /boot/initramfs-$(uname -r).img $(uname -r)` (for RHEL 7)
3. Reboot the system for the changes to take effect.
Note: Blacklisting the `amdkfd` module may impact functionality that relies on the AMD KFD driver, such as certain AMD GPU compute features. Evaluate the necessity of this module before applying the mitigation.
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.8 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: 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; Execute Unauthorized Code or Commands
Write operations could cause memory corruption. In some cases, an adversary can modify control data such as return addresses in order to execute unexpected code.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
Attempting to access out-of-range, invalid, or unauthorized memory could cause the product to crash.
Other
Technical Impact: Unexpected State
Subsequent write operations can produce undefined or unexpected results.
Frequently Asked Questions
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