SB2026072777 - Improper Initialization in Linux kernel vfio-pci runtime power management handling



SB2026072777 - Improper Initialization in Linux kernel vfio-pci runtime power management handling

Published: July 27, 2026

Security Bulletin ID SB2026072777
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Improper Initialization (CVE-ID: CVE-2026-64476)

CWE-ID: CWE-665 - Improper Initialization

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper state management in vfio-pci runtime power management handling when changing the disable_idle_d3 setting for devices already bound to vfio-pci variant drivers. A local user can change the sysfs module parameter and trigger unbalanced power management operations to cause a denial of service.

The issue occurs because the setting was latched globally at module initialization rather than consistently per device, creating a window where existing bound devices could operate with inconsistent power management behavior.


Remediation

Install update from vendor's website.