SB2026082880 - Improper locking in Linux kernel iommu iommufd driver



SB2026082880 - Improper locking in Linux kernel iommu iommufd driver

Published: August 28, 2026

Security Bulletin ID SB2026082880
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 locking (CVE-ID: CVE-2026-80687)

CWE-ID: CWE-667 - Improper Locking

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 lock release in iommufd_vdevice_alloc_ioctl() when validating the driver's vdevice_size against the core structure size. A local user can trigger the error path during a vDEVICE allocation operation to cause a denial of service.

The issue leaves the igroup lock held and can deadlock the next vDEVICE operation on the same group.


Remediation

Install update from vendor's website.