CVE-2026-43468
Description
A flaw was found in the net/mlx5 component of the Linux kernel. This vulnerability involves a deadlock condition that can occur when the eswitch_mode_set function attempts to acquire a devlink lock while the esw->work_queue is executing and also trying to acquire the same lock. This concurrent lock acquisition can lead to a system freeze or unresponsiveness, resulting in a Denial of Service (DoS).
Statement
This Moderate severity flaw in the Linux kernel's net/mlx5 component can lead to a system freeze, causing a Denial of Service. The vulnerability arises from a deadlock when the eswitch_mode_set function and the esw->work_queue concurrently attempt to acquire the same devlink lock. This issue specifically affects systems utilizing Mellanox network adapters where these functions are actively used.
Mitigation
To prevent the `mlx5_core` kernel module from loading, create a file named `/etc/modprobe.d/blacklist-mlx5.conf` with the content `blacklist mlx5_core`. This action will disable Mellanox network adapters, impacting network functionality. After applying the change, regenerate the initramfs using `dracut -f -v` and reboot the system for the mitigation to take effect. A system restart is required.
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)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Other); DoS: Crash, Exit, or Restart
Each thread of execution will "hang" and prevent tasks from completing. In some cases, CPU consumption may occur if a lock check occurs in a tight loop.
Frequently Asked Questions
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