CVE-2026-43305
Description
A flaw was found in the drm/amd/display component of the Linux kernel. A mismatched unlock operation for the DMUB hardware (HW) lock in the HWSS fast path can occur. This happens because the logic for determining when to use the lock differs from the logic for when to unlock it. When the fast path is utilized on systems without FAMS (Fast Access Memory Support) hardware, this discrepancy can lead to a system hang, resulting in a Denial of Service (DoS).
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 | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/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
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability,Other
Technical Impact: DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands; Modify Memory; Other
Depending on the locking being used, an unlock operation might not have any adverse effects. When effects exist, the most common consequence will be a corruption of the state of the product, possibly leading to a crash or exit; depending on the implementation of the unlocking, memory corruption or code execution could occur.
Frequently Asked Questions
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